As a long time Mac user, I'd have to question your decision to move to Macs if you're going to turn around and run Windows on them.
Parallels adds another level of processing. The program is running on Windows, which is running on Parallels, which is running on OSX. There is a performance hit for that - particular for something like AutoCAD and especially for something like Revit.
BootCamp runs Windows directly on the Mac machine. But then you've pretty much just got a Windows machine - not a Mac. To use any Mac programs, you have to shut all your programs down and reboot the machine over to the Mac side.
These are options if you're a Mac office and need to run a particular minor program that is only available under Windows. I actually have one Windows machine to run a few minor odd programs for which there are not Mac versions. That was the cleanest, cheapest solution to run them. But I don't get the impression that you're planning to use a bunch of other Mac software.
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Thomas Bank AIA
Owner/Architect
Simply Stated Architecture, P.C.
Lemoyne PA
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