If you're expecting toys that always work right, pick a different hobby. That said, a lot of retail shops offer solid warranty options so you can avoid personally dealing with the problems for awhile. IMO you should probably be looking at retail or someone on pinside with a lot of positive feedback for now. If you are getting into this just to play some pinball, buying some duct-taped constantly breaking turd off Craigslist will have you ripping your hair out(and possibly throwing it off the roof.) If you like to tinker, buy away, but it sounds to me like you just want something to play.

I've heard some questionable things about TNT, but do not have any personal experience.