Curt,
this is an often heard complaint on the other
train forums I belong to.
QC in China
Damage in shipping
First run locomotive design flaws

If you're purchasing from a LHS, they should
let you check out the locomotive,, to  make sure
you're getting what you pay for.

Online Train Stores,  you can't inspect the locomotive,
then having to ship it back if it's problematic or damaged
in shipping.

Online Auctions -A leap of faith... You pay your money & hope
what(if) you receive is what it was described as.
Again the possibility of shipping damage.
Then dealing with return or refund if it's not as advertised....

I'm not sure if it Caveat Emptor or You Pays Your Money & Takes Your Chances....