I've been using them for six months or so with zero problems, payment or otherwise.

For downloads, you have to download their allofmp3 explorer software. Once you have it, you don't even need the website anymore. It manages your downloads in the background, lets you search and browse with a much better and faster UI, and displays your current balance. The only thing missing is the recommendations/other people bought feature, which I kind of like. But you can hit the web once in a while when you're curious.

It took me two months to burn through the first $25 I spent there.