I wouldn't go with Mac. Most people use Microsoft Office, so using Mac will hinder you (even if there is a Mac version, it is probably less compatible than the Microsoft Windows version).
If you do want to use MS Office (no idea why you would), as you said there is a mac version. I'm not sure what you mean by being less compatible, but having owned it, I can tell you it is MS Office just simply on a mac (apart from a couple insignificant features).
...but open office is free and does all the same things anyway.