I'm almost certain that when you reset the DL's that you've previosly purchased from DAZ, the MAC version of Bryce is available also. Though what will you do with all your other software?

As dhama mentioned, there's going to be a learning curve to switch your OS.
I would ask people that have both or have switched, and even possibly sit down at a MAC store to test drive one. (bring your list of questions for the sales person)

Not sure what you plan on spending, though I can tell you from personal experience that My A-ware workstation is not as impressive off the showroom floor as they would have you believe.
I've made substantial upgrades and finally have a machine that can handle what I want / need it to do. Not to mention some major repairs at 4 months out of warranty.

BOXX looks decent, but I suspect the cost to get a high end WS from a "Brand Name" will purely be that, Purchasing a Name-Plate on kick-ass machine when you could probably build your own with some research for much less.

Overall.....Investigate pricing, try out as many pre-built systems you can get access to, talk to as many people as possible. Allow some lattitude for upgrading, IE: (build a good base system that you can add to). Read lots of online reviews for hardware, software, OS, system objective.

Write down and print out all the info you can gather up.....Doing all the homework first will pay off in the end. You have a good window of time to investigate.

Good luck, & Congrats!!
ICM

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Ockham's razor- It's that simple