Were these machines always so painful? Maybe I'm misremembering, or maybe age hasn't been kind to them.

[LaPorta]

Funny enough, the PT Pro I tried first had the fewest issues of all of them, though I didn't swap out the CPU or try to put OS X on it.

My PT Pro has a Sonnet G3 card in it as well replacing the original 604s. Never attempted OS X; I’ve got G4s for that. It works just fine and dandy with the ATA and G3 at the same time, though.