One nice thing was how seamlessly the thing was edited. I noticed only one (or possibly two) places where the audio jumped, because the soundtrack was playing. The three movies were blended seamlessly into each other, so it wasn't obvious where one left off and another began.
4.5 hours is a bit much at one sitting.
My only real quarrel with the edit--and it's a little one--was that the scene with the dwarves being treed by orcs was cut. That's in the original novel, but doubtless there was too much dialogue referencing the other cut material for the editor to keep it in.
But cutting about 95% of the material surrounding Azog was a good decision because all that pale orc crap is boring as fuck. It's almost as boring as the Necromancer shit was.
...you can tell what came from Silmarillion, that's for sure.
Oh--the encoding. It was a little jumpy, especially in scenes with a lot of motion. I don't really mind, and it ran well enough from the external hard drive I have plugged into the BD player. No complaint.
For me, though, this is going to be the definitive version of the movie. I still want to get the box set of the extended versions of the movies, and watch them once, but most of the reason I want to own that set is to legitimize (ie "pay for") this copy of them.
So, thumbs up.