Originally Posted by
Jadesfire
I've got an aluminum stem adapter with carbon spacers, which have been in place for ~ 8 months with zero issues... FWIW.
You're living on borrowed time.
OP- Are these reputable, name-brand crabon spacers, or are they generic Ebay spacers? Don't take chances with parts that undergo heavy loading like a spacer. That's a mistake you'll only make once.