Office for Mac has or had the tendency to be rather unstable (i've hears Office 2011 changed that, but that's hearsay)
Office 2011 is actually quite good, seems to be better than the Windows version TBH.
I went DOS>Windows>Windows + Linux (RedHat and a Russian clone of it)>Ubuntu>Win7>Win7+OS X
So far OS X beats the rest. It has the ease of use and non-involvement of Windows + under the hood power of UNIX (BSD to be more precise). That is to say I can still run iTunes without having to hax the balls out of it but still get SSH out of the box
@mpicco the main reason OS X requires a lot of effort to get working outside of Apple hardware is EFI. Most "PC" boards are still running BIOS and the EFI implementation on those that have it is fairly broken. The other problem is drivers, Apple doesn't make OS X drivers for components outside of their hardware (makes sense why would they?)
As far as buying a Mac to get OS X.... When Snow Leopard came out, I walked into Best Buy paid $30 for the DVD and walked out (also it's good for 3 machines IIRC could be wrong but its more than one for sure). Doesn't seem difficult to me
Back to Linux:
I have given up on Ubuntu when on my very old tablet just released Win7 was slower than current version of Ubuntu. The fact that my designed for Ubuntu XPS stopped recognizing the finger print reader after 2 updates and would take 2-3 minutes to connect to wi-fi after suspend while on win7 it took 15 seconds (and most hardware recognized out of the box) was just enough to push me back into Windows. The fact that BT audio is BEYOND complicated in Ubuntu (and I use it quite a bit) was just icing on the cake.
It's not a very good desktop OS, actually let me change that, it is a very BAD laptop OS. If you have a desktop that you are building yourself and know what you are going to use it for it's great. I have a co-worker who swears by MythTV (I use 7MC myself because it took me all of 30 minutes to set up 25 of which was Win7 install). If you do some kind of development work that doesn't require Windows and use an always on wired ethernet desktop that will never see any gaming or have to be used with iDevices or BT it's GREAT. Otherwise it can be a complete pain in the ass, which IMO is not really worth it.
EDIT: I never cared about RMS's hippie ideals of openness and freedom when it comes to software. It's not open code that we need (although it is nice to have) it's open and enforced standards and API's.