I've been doing fewer exchanges lately, but that's less because of any particularly bad experience, and more because I have other things to do and want to prioritize my own ideas more so I'm only signing up for ones that either have themes I'm really interested in, or where someone requests something that I'm actively inspired to write. A major reason I do them is because having a deadline by which somebody else is expecting the thing to be done definitely helps motivate me to write stuff, but I'd prefer not to need that all the time.