Althought I am a die-hard Mac user, I will say my two cents says go with what you are familar with. For me, its Mac. To do the things that I can do instantly on a Mac, I find that I have to hunt and peck forever to find where they are hiding those commands/whatever on a PC. I'm sure that PC users feel the same - things aren't in the same place, and things don't run the same. I hate it when my mother calls me to fix her computer - things that would take me seconds to do on my machine, I often can't do for her PC. I really feel like PCs are computers that are made to be used without questions. Its so hard to get into the control areas to fix/adjust anything. I will say that I have no problems touring with my Mac, I use MacLinkPlus for tanslating PC documents. It gives me a wide choice of programs that I can open documents from or save to their format. I also have PowerPrint - which provides me with printer drivers for virtually any PC printer I come across. So, I can walk into a venue, literally just plug into their printer, and print.
I just like having my own computer with. Its great to be able to sit and work with what I'm familiar with, while the folks around me are cursing their ancient donated computers.
-Centaura