RE: Alert: Bad Seller, do not buy from this person
Well of course RCU lost the other half of my reply.
Bottom line, if you expect .0001" perfection from a used engine, I think your standards are far too high for a used piece.
Additionally, I'll bet there are MANY honest, trustworthy, good sellers that have engines listed (and currently flying) that may exceed your exacting tolerances. Are they bad sellers? NOPE. Do they serve to have their names drug thru the mud? NOPE.
What happens if the engine you purchased ran perfectly fine in the previous owners plane? What happens if it never vibrated and ran perfectly okay but now you measure it and it has an issue? Did that seller rip you off?