Just finished my first project with ProjectFork on J 2.5. A very powerfull component, with excellent integration to the Joomla ACL, which makes for a simple and fast setup. Looking foward to the newer versions!
I've been following this extension since if first came out. They have narrowed it to a science if you are on a good host. No hassle or fuss, set your upload limit set up to 4mb, install, enable rewrite, rename htaccess, AND away you go!