I put these on some cheap strat I bought from a pawn shop (full upgrade going on).
Installation took 10 minutes with my unexpert hands.
These tuners work flawlessly. Top notch quality - german engeneering surpasses anything from the US imho.
Not cheap, but worth the price for an essential piece of gear that will outlast a lifetime - just as anything from Schaller.
And they're beautiful, too :-)