It looks massive at first but then you get used to it really quickly and you also think how great it is to have so much more sace on the desktop. Especially useful if you have programs with a million different windows or that need a lot of room.
I downloaded a few full HD performance demos from
http://www.demo-world.eu/ and it plays them no problem.
There is the 21" version but I would truly reccomend the 27" version, especially for movies too.