So I had a few weeks with the Cintiq and here are my comments about it.
Lets start with the Cons:
-Yeah it's bloody expensive, unless your a professional you probably shouldn't even think about it. Even I had a time justifying the price tag.
-Pen to Cursor lag. Yeah it's there but after the 2 weeks you get used to it, and your back to being just as accurate with a regular tablet. (along with people nagging on the thickness of the plexiglass to the lcd.)
-The right hand corners are useless / cursor jitters, there is about 5-10 pixel border you cannot cross, the left hand corners work but jitters. not a big issue, I use the mouse if something is ever dire in those meager pixels.
-Sensitivity to power sources. This is the first time I've seen horizontal jittering of pixels in a lcd. Basically imagine a old crt that worn, and the screen has become wavy. The same happens to a lesser extent. Most of it goes away after the monitor has warmed up and has proper calibration. Using a DVI connection reduces most of it. While suffers the most using a analog connection.
-Text is blurry vs Samsung 225MS in some instances. IE blue text on Black.
-Top 1/3 screen gets damn hot. It's like touching your cpu heat sink after turning it off for a minute. (uh don't ask how I know) Last time I checked lcds don't get this hot.
-quite a bit of a odd glare/glow when the screen is entirely black, otherwise the view angles are good.
-software bundle is still useless.
the Pros:
-20" inch screen looks like a 22" (maybe it is? I don't have a ruler)
-Speed increase. I never lose the cursor anymore, Know where exactly where I'm drawing.
-scrutinize sketches more, since I'm starring at the screen a foot away from me, instead of 1 1/2' to 2' away from me
-Stand and monitor rotation, less time finding a akward position trying to sketch a peculiar line
-realitivly quick learning curve going from a Intuos 2
-Takes up lesser space. Since I just have a monitor taking up the desk vs desk and a huge tablet.
Conclusion:
For the hefty price tag you could have a nice HDTV, Laptop, or bleeding edge PC. So definitely this is not for your avg person. I've had second thoughts about returning the Cintiq as the jittery screen and burning hot monitor almost made it a deal breaker. And for over 2 grand you would think this would a flawless product, but it isn't. (jittering is solved by the most part, but I think this shouldn't been a issue in the first place)
But there something about drawing on a screen that almost feels as natural as drawing on paper that nothing else on the market that could replicate is making me hold on too it. Although it won't make you a better artist, it will in some cases make your life easier vs a regular intuos user. A definite luxury for artists if you can afford.
If your planning to save for one, I would say to hold out maybe for the next generation of Cintiqs. But so far I haven't heard of any plans for new ones since the 20WSX is only a year old? Although I hear that the 20WSX is now discontinued from word of mouth of US retailers/blogs. If that is true I guess you only options now would be the older 21UX or the 12" ciniqs (new that is)
Overall I would give it 8/10