While Mac Pros are pretty beastly machines, especially the higher levels ones, if you are building this yourself or getting your company to buy you the machine with the i7 3930k and the Quadro card it will do much better. The workstation card will help a lot with 3DS, especially compared to the 5770 in the Mac Pro.
Compared to a high end desktop at a similar price the mac pro tends to lose, but if its a question of your company getting you a lower end workstation because its hard to justify configuring a lower end one, or getting a mac pro, that is where they come in handy and would win.
I am the one buying this machine, it will cost me around $3,100 australian with a Quadro 1000 card
(but I am thinking of going to the 2000) I just want to make sure that I am making the right decision.