Hiya,
Same as the other posters above, I use Quick Office Pro. I did try both apps, full paid versions (my job reimbursed me for both). I'm a full-time student & teaching assistant, mom to a kid with disabilities, and just insanely busy, and I found that it fit the bill for me the very best. I prefer the UI, I'm able to view documents and notes on them from the students I teach and the professor (who also happens to be department chair) on the fly and edit as necessary, I can review and edit power point lectures, and it syncs with my GDocs. I've also found that for me, it runs immensely better on my phone (Evo 4G, stock GB) than Docs2Go did.
All that aside, I was a Palm Pre user for 2 years, and have something of a grudge towards DataViz (Docs2Go).
This didn't really factor into my reviews of the programs, because I am more concerned with functionality than a personal gripe with a company, but I can't say I'm not happy that QOP worked better for me.