We have 3 of them and love them. Surprised by the comment about the UI being a PITA, it seems brain dead simple. You can go from the Home screen to watching a movie in Netflix, Amazon, etc. in like 3 or 4 clicks. The UI is very responsive and I'd go as far as to say it's quite nice.
On our main family room TV we really only use it for movie watching (the Roku UI for HBO Go specifically is far quicker and easier to start up a movie then navigating through my cable box's on-demand for HBO) and occasionally Pandora. But for our other 2 TV's we use it for all TV watching; We have Time Warner cable and they have a Roku app which means that we can watch all of our Time Warner channels on the Roku which eliminates the need for a cable box on our other TV's.
The other thing that's EXTREMELY cool is the universal search. So say one day you feel like watching A Few Good Men. You just search for it and it shows you everywhere it's available (Amazon, Hulu, Netflix, Vudu, etc.) *and* the price for each. So it might be $2.99 in Vudu and Hulu but free with your Amazon and Netflix subscription. It just returns a big list of everywhere it's available with its price next to it. Super cool and a feature we use a lot.