In defence of the X800...
We've got two: one downstairs in the sitting room and another upstairs in the movie room.
When I got the first one seven or eight months ago now, it locked up twice, I think, but with firmware updates installed shortly thereafter, neither has missed a beat.
Picture seems superb, although I confess there were no opportunities to do side by side comparisons with any of the competitors. But at the price we paid ($150 plus tax) I have absolutely no complaints.
Sound seems fine too. If there's a limitation in either of our setups it will be the modest Yamaha speakers used.
Build is distinctly better than any of the Samsungs, and probably as good as the Panasonics. Remote is good enough: load, play, fast forward, rewind, etc. - what more do you need? Two things that do irk me are 1 the full width loading flap on the front and 2 that it only has a power and a play button on the outside. You need the remote, therefore, and if its gone down the back of the sofa you're Donald Ducked.