iWork is absolutely terrible from experience as well. It's not possible to effectively work with others, the UI is horrid and unproductive and it's completely unmaintained.
Microsoft Office 2011 for is pretty much close to perfect, and is certainly as capable as Microsoft Office 2010 that I run on Windows 7.
I run them side-by-side all day (PC Desktop with a big honking Monitor, Mac Laptop, 13" screen) - and I don't see any significant functional/usability issues with the Macintosh version.
Ironically, Microsoft Office is not a reason to use the Microsoft Surface instead of the MacBook Air. In fact, I'm willing to wager it runs better on the MBAir than it does on the surface. (Keyboard on MBAir laptop is probably better than one on Surface)