Looking into building up a frame that's BB30 compatible. Correct me if I'm wrong, but from what I understand there's only two specific BB30 compatible cranksets (SRAM and FSA). I've only used Shimano and Campy in the past (and for what it's worth have been equally pleased with both).....would I be out of line in using an adapter to make it compatible with Shimano or Campy or cranksets?

In using the adapter do you lose any of the drivetrain stiffness afforded by a BB30 specific crankset?