I have one of those ebay ones too. So far so good. You can set it to take anywhere between 1 to 99 shots and if you set it to 0, it goes forever. It would be nicer if you could set it to a number higher than 99 though.
I still haven't managed to get a half decent result yet... but it's fun trying, and clouds aren't always a show stopper.
http://www.youtube.com/watch?v=yp8vIwEkuK8
James