I don't know if dirty is exactly the right word.

I think by far most kindle re-sells probably go off without a hitch. People are just far more likely to post about their bad experiences than report on a non-event.
Thread Title: I bought a used Kindle and ..... it works just fine!
It just doesn't have the drama.
I personally wouldn't go to that much trouble over it because it just isn't worthwhile anymore in my opinion. You can get a brand new
with warranty Kindle for under $100 now. But if somebody that I recognize around here wants to offer me a Kindle Keyboard for $20 with the promise I can send a Moderator after them if I can't register it, I'll paypal you the funds asap.