Okay, digital piano owners need to try PianoTeq. (http://www.pianoteq.com
I'm sure some of you are familiar with this already, but I haven't seen any discussion on this forum about it. Simply put, it's a program that doesn't use recorded samples to recreate a piano's sound. It simulates how the physical components of a piano interact to produce all the sounds that a real piano can produce. By doing this, it's able to capture a lot of the resonances, harmonics, etc. that aren't captured when separate note samples are played together. Of course, it's not perfect - this kind of thing never will be, but it's getting really really good. Regular digital piano voices are comical by comparison, and if I could compare a PianoTeq recording to a "clean" acoustic recording (ie. no squeaks, coughs, recording hiss, or other artifacts) I'm not sure I could tell the difference.
It also lets you modify properties of the piano that are normally only available to tuners, mechanics, or restorers - things like tuning, temperament, unison width, octave stretching, hammer hardness, sound board impedance, string length (up to 10 meters!) etc. The "Pro" version even allows you to control many of these parameters for each individual note.
Most of my adult life, I've been looking forward to "one day" owning my own grand piano (probably one of the Steinway models) but now I'm not so sure. I spent around $3000 for my Roland digital piano (chosen for its action) and a little over $300 for this program (whatever 250€ converts to USD) and made a dedicated piano computer from spare parts, and I have a piano that feels and sounds like a reasonable grand piano. It doesn't have to be tuned or voiced (I can change them with a few clicks) and it doesn't have to be maintained, apart from the physical keys and computer parts. But honestly, I can go through several digital pianos and computers before approaching the cost of the grand piano I would otherwise want. I don't have to worry about temperature or humidity or sunlight or acoustics. Well, acoustics are simpler at least - position the speakers and the rest is part of the piano software. Most of the time, I go for what it would sound like sitting in my living room or a small studio, but I can record performances to MIDI using studio settings and then re-record using concert hall reverb and mic positioning.
Go listen to the demos and download the trial version (it's fully functional but it leaves out a few sparse notes on the keyboard). It's worth the time.
EDIT: Hugh Sung can explain it better than I can: http://www.youtube.com/watch?v=jTbXnbfymdc
, part 2: http://www.youtube.com/watch?v=ulS-N6PSRuc&NR=1
(Note: He's demoing a very early version of PianoTeq. Recent versions are even better.)
Disclaimer: I don't work for or have anything to do with Modartt, the company that produces PianoTeq, apart from being an avid fan.