@Jen
The biggest concern for me, is hygiene. The responsibility for wearing a belt isn't just for what your parents want, but for you to remain safe, by staying healthy hygienically. My alternate main concerns are mobility, as if someone needs to move you around if you're unconscious, especially if they need to give you a piggy back ride, but you can't because of thigh bands. You did list plenty of bad things about the chastity belt, but like anything you own, you need to be responsible of how it's used. Your parents sound strict since they first mentioned the belt, but I really hope you'll be ok. Do NOT wear the belt until you are 100% sure, or you will face regrets.
As others have mentioned, keep a pro list, since looking at positive outlooks would help you cheer you up rather than seeing the chastity belt a completely negative device. I'm sure there are a few pros, but make sure they outweigh the cons. Do as you see fit, but the final decision is ultimately up to you.
EDIT: Thanks Max9.
