You should use as fast a mac as you can get your hands on.
Running a VPC on my Imac(G5 1.6Ghz) runs at about the same speed as a PIII-900-ish.
I only ever use it for testing. If you want to use it for any actual work, grab one of those ridiculously cheap dell things and use that instead.
Josh Osborne - Central Innovation
HP Zbook Studio G4 - Windows 10 Pro, Intel i7 7820HQ, 32Gb RAM, Quadro M1200