I'm pretty new here and have soaked up info like a sponge. Initially, I bought a device without knowing about this site or about a proper fit. It was too long and too narrow. After reading that most men overestimate their size and should go smaller, I ended up with a cage that kept my penis a bit folded and created a chafing sore in the fold. Too short. After a few device experiments, I've finally found one that doesn't chafe and allows my penis to rest comfortably without becoming distressing if it decides to try to get hard. In fact, I don't even realize it's there unless I have to go to the bathroom or I start to get an erection. If your device isn't comfortable, figure out what isn't working and look for a device that meets all needs. It shouldn't be painful or uncomfortable unless it's intended to do so or you're getting erect. BTW, the Chinese devices are not mix and match between rings and cages, as has been implied; none of mine will mate with parts of the others, even if they seem to be the same style.
I've had several chinese devices supposedly the same product with either different sized ring or cages in my quest to get the closest fit before going to a custom cage( will be Xmas present) Non of those cages have been interchangeable at all
First time I got one that fitted well I too made the mistake of telling my then wife that most of the time I hardly knew it was there. She soon put that to the test..... for 3 months. Now of course 3 months is just the time between haircuts, not that I'm complaining.