That's the part where I can be most unbiased perhaps. I have ordered my Kawai CN 21 online, so it came in a box to self-assembly. The parts were brilliantly secured in the package, so no harm could have ever come to the piano during transport. Also all parts were easy to fit in place - it looks like Kawai really paid attention to details, because it's up-to-single-milimeter perfect. Sides, back and pedal units fit perfectly, just as the keyboard unit on top of everything does. The mahogany varnish is even and really nice, I couldn't find anything I could say was wrong. The keys are lined up perfectly, with no single on sticking out - also the action is flawless as far as I can tell. Overall, I'm _very_ satisfied with what I got from Kawai.
I'm not a professional pianist, I have never played on any grand piano - only on some inferior uprights that were out of tune and so on, mainly at my high school. I can't compare the action to the Steinway or Bosendorfer then. I have, however, played a lot of Yamaha boards (except CLP280 - which means except natural wooden keyboard) and I think I prefer the Kawai way of doing things. It's a bit lighter than Yamaha GH keyboard (just a bit), but feels more responsible and easy to handle. The keys are not stiff, which was the feeling I always had playing Yamaha. Please take all this with a grain of salt, because as I said, it's just my personal opinion. The keyboard is much to my liking, which I am very happy about, because I have ordered Kawai without ever trying one, just by guessing it's different from Yamaha I don't like that much in that particular price range.
After first turning the piano I was a bit surprised. The sound was quite sharp and very bright. After few minutes of playing it eased a bit, as the sound system had to break in. It now is even through the keyboard, with no notes sticking out in terms of sound. It is, however, still much brighter and on the high tones side than for example sampled Steinway from Akoustik Piano. I guess that's because Kawai Shigeru Grand is. I find myself to enjoy the sound much after few hours of playing. There are four piano sounds - Concert Grand, Studio Grand (a bit more focused and thin), Modern and Rock Pianos. The latter two feature less bass and even crispier tone. I really like ragtimes, blues and other contemporary music styles played with these tones. The Rock Piano, however, may sound a bit metallic sometimes. Overall the sounds are impressive. In my room (which is about 15m^2) the piano fits well and without any problems with bass or something. In fact, after next hour I like the sound even much more - to the extent I'm not going to buy additional MIDI2USB interface, as the sound satisfies me enough not to use Akoustik Piano anymore right now (but I guess I will eventually hook up the Kawai to the computer, e.g. for recording).
I have read somewhere on the forum, that it was impossible with Kawai to press a key without sounding a note - it actually is possible without problems. There is no sympathetic resonance though - you can't produce rich overtones e.g. by holding silent D in second octave and then pressing D octave higher.
Kawai features three pedals - soft, sostenuto and damper, as a real grand piano. The damper pedal supports half-pedalling which works really great. The soft pedal has also noticable effect on the sound, which sometimes doesn't really happen with digital pianos. Is there anything to say more about the pedals? They work and they are traditionally-shaped =D
If I had to make the choice again in the 1000EUR price range, I would definitely go with Kawai CN21 once again.
Photos are here: http://private.maticomp.net/kawai/
If you have any questions regarding Kawai CN21, feel free to ask. As I'm not a professional pianist, I may have missed something important what should be mentioned in the review. Of course I will be happy to help with any issues and questions regarding the piano!