I did a lot of research on them Dan, and bought one.
They certainly can be problematic, you should read up on w w w .rimfirecentral.com before picking one up. I hear the new ones are great, '05 and '06 manufacturing dates, the earlier ones have a few bugs that can be fixed, or lived with.
Myself, i bought an '04 used, knowing what they are all about, and the only complaint i have so far is the odd empty casing flying at my head. And i remember reading some where how to fix it, i think i need to tweak the extractor spring.
I shot just about as tight a grouping as with my S&W 22A, which is also fun to shoot.