On my desktop I'd chosen to just keep the free starter office, but when I bought my laptop I decided to upgrade. Definitely worth it, especially as it was three licenses - one for my laptop, one for my desktop and one I gave to my sister.
Only two cons:
1. In upgrading from starter my sister has had some trouble with her recently opened list not pinning to the menu. Apparently a common problem with upgrading.
2. I had an older version of Word previously and now I must admit there are some features that I struggle to find - I know they're there, but now in an odd location, which can be somewhat frustrating at times.
Aside from that it's Microsoft Office, what more is there to say? To my mind it's the only way to go for word processing and spreadsheets.