It's entirely reasonably to run Windows directly on the system via Boot Camp, rather than running it in a VM.
If you handle many Mac cases, you certainly want the option of performing forensics using another OS X system, as properly analyzing some Mac data is restrictively difficult from a Windows system.
I don't understand the need to use a MacBook Pro for forensics.. Keep it simple..If you used a Mac Based forensic software use it..if you us a Windows based Forensic software then use a PC.. the less Stuff running the less complicated it get's and the less problems you will have.
I use it for flexibility on collections/imaging. I can run three different OS's on one piece of hardware natively (OSX, Windows, and *nix).
And I prefer working on Macs. But I still have a Windows machine that I use for dedicated analysis.
Tom
Holy thread resurrection!
I am pretty much an all Mac lab. My Macs are set up OS X and Bootcamp usually with a few VMs (Windows, Linux, Linux Boot Disk distros, etc). I use one of the new trash can Mac Pro's in the office for DFIR work - been super happy with it. I use an MBPr in the field and wont go back to anything else unless Apple screws up what they have. I like to work on Mac images with a Mac for EA's which are often misunderstood or ignored my PC based software. I get about 40-50% OS X now for exam.
You do pay more in buying Mac compared to a comparable Win box.
Whatever storage type you are using for your images, make sure OS X can read/write if need be. There could be "driver" issues for writing to NTFS from OS X. There are lots of third parties out there though who sell or offer these "drivers".