A post I made recently on my Wordpress blog got a comment that I gave a partial answer to. I don't think I've written much on chastity in the past year so I figure that might be a topic to revisit.
My older version of writing would probably have taken the pros and cons and presented them in an infomercial-esque way, talking about the potential benefits of chastity in a relationship, and so on. This time around I don't really feel like going that route and will present it from a more personalized outlook.
The comment I am referring to basically asked if I needed a device to keep from going out of control with my genitals. That is an easy answer, no, a device is not needed to do that. There are many terms for male subs that are unwilling to give up sexual control and/or follow the rules of said sexual control through their own willpower... and few of those terms are kind. If you have been in or practiced a serious Femdom or FLR type relationship, your ability to jerk off whenever you want to likely went away very quickly. This sort of goes with the territory.
I've always felt that chastity wasn't a replacement for the honor system or self-control, but something that works as part of a control dynamic that one or both parties finds enjoyable.
I actually enjoy chastity (within reason) quite a bit. Part of it is because I am drawn to women who really embrace control dynamics. If locking me up and tucking away the key fuels her Domspace and gets her juices flowing, great! This serves as one more thing that can be held strictly under her thumb.
One of the things that appeals to me most about chastity is that the sexual frustration is exquisite. It's very difficult to describe and brings about an entirely new set of feelings, awareness, and emotions. It's so easy for us to take erections for granted and at inappropriate times we can even attempt to tune them out and/or clear the mind. Most guys have a pair of pants that makes them more aware of the tent they are pitching during an erection as the pressure of the fabric pushes against the direction your penis is moving. With a chastity device on, you get that "attempting to pitch a tent" feeling but it can just go on and on and on, providing just enough pressure for it to want to keep trying but it has nowhere to go. It's pretty much impossible to ignore this when it is happening and that is the source of a lot of other emotions.
There is kind of that natural human impulse to want what you can't have. Fighting to have an erection that will never happen makes you want to have it even more and/or touch it. You also become very aware of just how many erection attempts you have in a given day. You can't just shut it off and time drags while it is happening, fueling both passive and active submissive thoughts. From a subspace perspective it reminds you of her control over you. From a loving perspective you will start thinking about her a LOT. Even if it starts out because she has the key, the thoughts can become almost obsessive and it's quite common to think of things that would make her happy. e.g. picking up some flowers and candy on the way home from work.
A byproduct of all of this that happens with some women (but not all), is that she will enjoy the idea that you can't get erect that she will go out of her way to get you to attempt an erection. The extra teasing, sexual tension, and attention can be quite enjoyable and bring the intensity to new heights.
Based upon what I have read and the subs I have talked to, I believe these parts aren't all that unique among subs in chastity.
There are a couple of aspects that are unique to me. One of which is that I have a fairly libido. While I enjoy a lot of activities that may be perceived as sexual, I have a fairly low craving for sex and if I had a stressful day or am in the midst of nerding out on a hobby, my sex drive and attentiveness diminish greatly. A chastity device builds up a lot more unavoidable sexual tension and my cravings and desires tend to grow with it. It can be a bit of a contrast, going from thinking about sex 0-2 times a day to 20+ times a day by the addition of a device. It's kind of silly but it's true.
The other aspect is that when my depression cycles up my sex drive falls to virtually 0. If D/s dynamics aren't going regularly it's common for me to not even have the desire to masturbate for ~3+ weeks at a time. A chastity device changes that and the awareness it brings tends to keep me in a more positive mental state (subspace) which actually counters a lot of the normal effects of my depression.