I'm only an occasional wearer, and have no interest in keeping myself chaste (not does anyone else, as far as I know 😮) But I have some devices that I have experimented with a bit, so I'll share my conclusions here.
1) Leather chastity shorts (like: https://www.ebay.com/itm/194289354737) - obviously only a fetish item: needs to be partially unlocked for any toilet visit. You can still rub yourself through the leather, although I don't think it is easy to orgasm, and if so, it will leave a mess.
Comfort: reasonable; security: meager
2) Chinese CB-x000 copy (like: https://www.ebay.com/itm/185071889936) - One very weird construction thing is that the ring behind the balls is shaped like an H, with instead of a rounded surface, there are two thin edges pressing into the ballsac. In the end I filled them up with tissue. For the rest the construction is not great either; with all the parts you have to assemble, there is a big risk of pinching the skin, and hairs getting caught (if you're not shaven). It came with several spacers for the space between the tube and the ball ring, but with a spacer that was comfortable, I have managed to get a fully flaccid penis out, and shorter spaces got painful quickly. When I recently tried it again (I've had it for years), it spontaneously broke at the seams. Superglue seemed to fix it. The padlock can rattle, but I put an elastic band around it and that removed most of the noise.
Comfort: low, security: low
3) Chinese metal wire belt (https://www.ebay.com/itm/114826355599 option #2) - I have not been able to adjust it so that the solid metal part stays tight to the body, and I always manage to roll it to the side, and take the penis out, even when I put the wires so tight that there were deep furrows from wearing it after an hour or so. And with the metal part hanging a bit lower, there is also rubbing on the thighs when walking. For the penis it feels more comfortable though than a cage. I've tried it lying down (about 30 min), and could find no position that the belt prevented or started hurting. So unless I can find a different way to adjust it, and it sits better, my judgment is:
Comfort: medium, security: very low.
4) Chinese Holy trainer V4 clone (https://www.ebay.com/itm/115007072013) - I got this when my CB-x000 cracked, and it is a major update in comfort. I got a size max though, which was probably a mistake. It makes it easier to put on if you're not completely flaccid, and I expected it a bit less uncomfortable when trying to get erect, but the length of the tube makes you need a very low crotch on your pants; otherwise it will be pushed upwards and put pressure on the skin of your ballsac. Because the ring is anatomically shaped, it normally lies very close to the body, stretching the ballsac less than the CB-x000. The internal lock is rather simple, and probably quite easy to pick. The official holy trainer should be a lot better in that aspect. But other than that I have found no way to escape it or pull out.
One thing that could be a downside for some is that the key is also needed to lock it, unlike ones with a padlock, but on the plus side there is no rattling of the lock. All in all a lot of value for under 10 Euro, although for 24/7 you probably want the real thing. (This one could help experiment with the ring and tube sizes though.) There is a nice comparison between knockoffs, v3 and v4 models on Reddit.
Comfort: medium (probably better with a smaller size), security: medium
