Midwest Hospitality Group a hotel syndicate I used to work for loved it. They had it on all of their systems and it worked as well as MSOffice and saved them thousands.
Yeah it's the best one out there. There's even that portable version you can throw on a flash drive--I used to use that at slow days at work all the time. Written lots of papers on it for school.
If your looking for an online alternative, so your documents can travel with you, check out zoho or Google Docs at http://docs.google.com . Both provide similar tools as ms office, but with the convenience of being able to access them from any computer with an internet connection. OpenOffice is pretty much the best alternative as far as a complete software suite though.