What can go wrong when flashing an unstable Android OS onto a phone? Is there an easy way to reset the phone if something goes wrong? Has anyone out there had experience flashing Android OS?

Is it a good idea to flash Gingerbread 2.3.3 aka Leaky onto their Samsung Epic 4G?

One benefit that I can see is that users of the Epic will be able to test their applications on > Froyo 2.2.1, which is currently the stable release for the phone.