"A MS Office license would be a wise investment."
Alas (sic.) no.
MS Office for Mac is
less compatible with MS Office for Windows than NeoOffice/OpenOffice - as I have found to my disgust.
NeoOffice/OpenOffice isn't cheap, it is
free - an excellent cross-platform office suite used by all the people in my practice with much satisfaction.
Try it, if you don't like it you have lost nothing and you can then shell out much bucks for Microsoft's bug-ridden, insecure, overpriced and proprietary file-format effort.
Mac
(or get Apple's excellent iWork - if you get it with your new machine it'll be cheaper [and better] than
MSOffice for Mac and it'll read/write and import MSOffice for Windows files nicely)