Just wanted to chime in with my (by my account) non-professional opinion.
Ordered this due to the great deal (and service) by PP. My trusty old Sony hs10 finally died (well, it's blue chip burnt away just enough to make everything yellow

)
Was considering the Epson 8350 and the Panasonic 4000 (with, unfortunately, limited availability to view either for very long). Was then considering the more expensive 8700B
The was purchased for a room painted black, light controllable (although it pulls double duty and sometimes has a small /moderate amount of lamp/ambient light) with a painted screen; a HINT of neutral-ish grey.. maybe n8.5 at most
Projector is about 10.5 feet from the screen, set to 104 inches (pulled back a smudge from it's full capacity).
So far: VERY pleased. It honestly has surpassed my expectations. The only negative I've read about... 'blacks aren't deep enough'... is really not fair. Perhaps on paper or to someone who is absolutely beyond anal about their Black Levels it might not be 'perfect', but after reading about the blacks levels I was shocked at just how good they really were. The hint of grey on the screen helps even more, but even on a white wall, they were MORE than decent. With the lights out, as Spinal Tap would say, there was 'none more black'.
More importantly, the levels of black to grey to white are outstanding. Let's say that the reviews are to be believed and the black level does not match projector x or y, when there are scenes where there are shadows, a cave, etc, details on the 181 are EASILY seen, even when the projectors settings are skewed towards cinema/darker levels. Bottom line: even if you feel that the 'scene out in space' is not black (again, not really fair... they looked wonderfully black to me), the other, more important scenes with shadows, lights, etc look great.
As many reviews noted, the projector has a wonderfully warm, almost 3d quality to the image. it really 'feels' like a movie theater image. Getting back to the blacks, I loaded up the bluray of the 'gold standard' fifth element. The black berets were stunning... you could literally make out the threads and material, shadows were easy to see through, the black outfits were stellar looking, space was BLACK, and everything look vibrant yet believable.
When you're NOT shooting for the blackest blacks possible, this thing is BRIGHT. Im talking two lamps on in the room and it's as bright as a flat panel tv bright. When you first take it out of the box, and it hits you with it's Dynamic mode, it's practically blinding.
I picked up one of those Sony Google Tv Thingees; When you load a blank white google page at 104 inches, you literally have to hold your hand in front of your eyes.
When dropping it down to cinema mode and getting it to GREAT black levels, It was still more than bright enough to handle moderate ambient light; Yesterday while my wife was reading, I realized how bright the image was with lights on in the room; I had to do a double take when I realized that I had set the projector lamp to LOW. Bottom line: For MOST of your viewing you can probably set the lamp to low thus extending your hours.
On the negative side, I have noticed 1-2 seconds of stuttering once or twice in the five days I've had it. Nothing deal breaking, and nothing that last longer or repeated itself; I can't even swear it wasn't my receiver, but thats the only 'complaint' so far.
Trumotion seems to work well, but the 'Soap Opera Effect' drives me NUTS, so I honestly have no interest in using it. I'm so glad I found the phrase 'Soap Opera Effect' and it's meaning; I had assumed I was going insane when I noticed it on my brother's TV ;-)
Hope I didn't bore anyone! I had spent weeks on this board doing research, and wanted to give back a bit.