I have tried a few chastity devices and have finally found one which I feel is perfect. The BON4 is comfortable enough to wear long term for those who are going to take chastity seriously and not just as sex play. I found that the CB3000 ect were ok for short term sex play but after a short time started to become uncomfortable and chafe. Also, if you wish to wear your chastity device long term, some like the cb3000 shows like crazy under clothing.
Firstly I would point out that the BON4 is a bit tricky to get on, much harder than the CB range but with a little practice, it’s soon simple. I would suggest some baby oil rubbed into the cock and balls, the hands wiped and then push the balls through the security loop one at a time, then the cock. Try the 3 different size security loops and see what fits best. This, like anything is trial and error. Once the security loop is on, the rest of the fitting is as easy as putting on a belt. Feed the plastic fixing strip though the 3 slots , pop the holding pin in place and then tighten to what feels good for you. DONE. The whole thing can then be tightened even more if wanted to really punish the wearer or just for a very snug fit.
Being silicone the BON4 soon become part of you and after a short time you will start to forget it’s there. But when it comes to sexual thoughts, erections and masturbating, you will soon know it’s still there .I have worn mine for extended periods and found cleaning is easy, its comfortable, ( except when getting erect) and is by far the best male chastity device for those wishing to take chastity seriously. Great job BON4
J. Keane, UK, Jan. 4/2012

Awful. can easily slip out even with the smallest ring on. even if you dont have the key it doesn't really matter. the silicone is soft. i could, with little difficulty, cum while the device was on.
Ted, CA, USA, Jan. 3/2012

I'm giving the Bon4Plus, a 4 out of 5. It is very comfortable. I am sure I could pull out of it, but do not think I could get back in. So, in that sense, it does it's job. Mistress and I talked about chastity for a while before She selected the Bon4 for me. I live about 4 hours away from Her. She liked the idea of me being in chastity between visits. Longest lock up has been 21 days. Now doing 10 days before She says I can have a break. She says that starting January 1, I will be locked up for "at least 7 weeks"!! I'd recommend the Plus, because you get the 4 rings and two tubes. This is my first time wearing a device, and not having the keys to it. Years ago, I tried the CB2000 and it was very uncomfortable.
Subman, USA, Dec. 30/2011

The BON4L is simply a great device. I was a bit skeptical in the beginning especially when I tried to put it on. After 2 or 3 times you know how to put it on, use a lub is really the trick. You can pull the flexible silicone cockring of your choice much wider open which makes it all a lot easier. My mistress is crazy about the sexy look of the penis shaped cage, and what she loves I love too! I am wearing the BON4L now for 16 days without any problems and I will mail an update later. I will tell you guys a secret (they will probably remove this text) but I found out later from a friend of mine that if you purchase a BON4 by clicking on a banner from them on the fetlife.com website you get a bon4plus for the same money...
Jorien, Amsterdam, Dec. 23/2011

"well my fiance has trouble with me wanting sex all the time and so i went a got 1 Bon 4plus then she can lock my penis until she wants sex then unlocks it when she wants sex. its so great i love it, every male should get 1"
Jonathan, Belgium Nov. 22/2011

"Just got it, this BON4L is my second device. The first was metal and was too small. I guess I have large balls because I keep reading about other people wondering why they included the largest size. I have to wear the largest and just so I could get one ball at a time through. I was also not happy with the bulk of it. Don't think I will be able to wear in public unless I wear somewhat tight jeans to hold in. Wife is excited sand that's what really counts now isn't it. I don't have a key so why bitch, just enjoy!!!!!"
Will, Uk, Nov. 11/2011

"I recently purchased the Bon4 Plus, I find it superior to the main competitor; it is easier to get on than the one piece offered by Birdlocked, although being two piece and with a potential to trap skin initially, we found that it makes for less wear and tear on the device, we have already ripped one Birdlocked. The Bon 4 is suitable for those of a larger circumference than that offer by others, it is comfortable to wear for long periods and is impossible to remove and replace without unlocking, trust me I have tried. My girlfriend and I would recommend the Bon 4 to anyone who is interested in serious male chastity play."
David, Canada Nov. 10/2011

"I have had the Bon-4 for a little over a month now and my SIR has put me into chastity for the third time now. The first was for 10 days, the second was for 7 days and I am now on day 3 of a 28 day stretch. I guess the good news is that it is pretty comfortable for long stretches of time but it does take some getting used to. The first 10 day period resulted in some very chafed balls and severe discomfort. I learned on the second time in chastity to use some A&D ointment where I started to feel chafing…this has helped immensely and made wearing the Bon-4 tolerable…where you’re not walking around wincing at every step. The key is getting the cock ring sizing correct. I have large balls but an average to small size cock that is a grower not a show-er. I used the largest ring the first go round to accommodate the balls and in the middle of play on the 10th day, the thing just fell off and my SIR and I still can not figure out why. I have since moved down to the middle ring size and have not had a repeat of the problem. Because of my cock size, I can still get somewhat hard while locked up and would suggest a sheath size option in addition to the cock ring size option. I will update the review after being locked for 4 weeks."
Sir's Boy. USA, Nov.7/2011

"Very fiddly to put on, don't expect your partner/mistress to put it on for you. I needed to attach a cord to my P.A. piercing and pull it on . Don't forget silicone based lubricants will damage this chastity device. Not as comfortable as you would expect because the cuff ring, although narrower than the 'bird lock' is still quite wide however, it is a little more comfortable at night and when the penis is aroused. The cage comes in two sizes although, I'm not sure who the smaller cage would fit because I even find the larger cage a bit small. Could be a little bit longer because unlike other chastity devices the cage section measurement starts directly from the cuff ring and does not have the availablity of spacers to give the additional length as does the 'Curve / 6000' and some metal chastity devices etc. I also thought it was very expensive compared to the 'CB 6000' and the 'Curve' however, I have seen the same a little cheaper on E Bay and in Europe, which puzzles me because the Bon 4 it is apparently manufactured in the U.S. ??? As a male who has now been in chasity 24/7 for approximately 85% of the year and have been for about 12 years I believe I have the experiences to give a reasonably good overall review."
Michael, USA Nov. 2/2011

"I have tried other male chastity devices, and with all I've been able to manipulate it enough to reach a slight orgasim. Also, at night, with ball shrinkage, I've had both the CB-6000 and one similar to the chrome plated chastity tube slide off. Not with this puppy. My balls usually sit rather tight up against my body, so putting the Bon-4 on is not the easiest thing. Once my balls are through the largest ring, I have to work to push my penis through. Once both are through, and the cage is attached, WOW. I'm stuck. The silicone ring doesn't move, it grabs. The cage, with the bottom attachment that splits and spreads the balls is actually the secret to this thing staying on. With your balls spread wide, there is no way they will go back through the ring. Your results may vary, but my girlfriend is satisfied that I'm not getting out until she's ready. Even though the silicone cage allows you to squeeze the penis and feel it, there is no good way to get any movement going that would come close to what I need to orgasim. Diabolical little thing. Enjoy."
Leroy, USA Oct. 12/2011

"Have tried CB-xxxx devices, and now this Bon-4 device. The Bon-4 is the most comfortable to wear, but (sadly, I suppose) even with the smallest diameter ring, I am able to pull out and remove the device completely with relatively little effort. I haven't, however, tried getting back in to avoid possible removal detection. That will be something I'll try soon."
Kees, The Netherlands Sept. 25/2011

"Mp penis is very small measuring limp 2 inches. Finding a chasity device has been extremely difficult. My wife has been controling my penis even before we were married. We have tried several chasity devices only for me to slip out. Since she purchased the Bon-4 I am totally confined. I am totally controled."
Duncan, UK Sept. 11/2011

"Awesome!"
Brad, USA Sept. 2/2011

"I bought the BON4 a couple of months ago and have used several times. Is difficult to but on compared to other models and the wide ring really puts alot of pressure on the balls. Also had a problem with one ball slipping through if I wore it out in public with all the moving around. This device would be great for someone who has low riding testicles and and average size penis"
Mitt, USA, Aug. 23/2011

"this gives a whole new meaning to the old ball and chain, any man who let a woman control him to that point of submission would get the best blow job ever from me over and over again, this is gonna be a great holiday gift,and tonite when my old man gets home we are doing some shopping..."
Tracy, UK, Aug 3/2011

"Pros: Extremely comfortable Flexible More secure than the CB series belts. Unable to put device back on if escaped Easier to keep sanitary while showering

Cons: Allows stimulation through the device Escapable with a bit of work holes on the side of the head can cause a mess when urinating Slightly bulky, can create a bulge in tight pants (Can be mitigated by pushing the head back towards the ass) Ive had this device for about 3 weeks now and I've only been out of it for 1 day during that time. I've been able to do all of my normal daily activities with this device including some very close dancing (without detection!). Overall it's a very comfortable device and a good value for the money."
Karmic, Germany, July 21/2011