I haven't seen the new RCA LCOS set (is it even in stores yet?), but I did have a chance to demo the Panasonic 52" DLP/RPTV.
It wasn't very impressive. The resolution was high... no visible pixels, no rainbows or screen door effect. However, it had poor shadow detail and very gray blacks. If you saw the set by itself, you might be impressed. But the store made the mistake of setting it up right next to a Panasonic 42" plasma, and the plasma ate the RPTV for lunch. With the same HDTV source, the plasma looked more like a window to the outside world, with lots of shadow detail and deep blacks. The Panasonic DLP/RPTV looked like you were viewing through a thin layer of fog. The RPTV seemed to be reasonably well calibrated, so I don’t think it was just a poor setup. The image reminded me of lower-cost LCD and DLP projectors that haven’t been tweaked to beat the black level problem. And it wasn’t helped by all the usual encumbrances of rear projection (ultra-short focal length lens, screen diffusion, etc).
The Panasonic DLP/RPTV did have two nice features: the lack of screen burn with letterboxing or station logos, and a thin case design. I think these new DLP/LCOS sets will make a dent in the RPTV market just because they have a smaller footprint and weigh less. But the price has to come way down, and they need to work on the black levels.
If your client doesn't have the ambient light control or space for front projection, then I'd steer him or her to the new Panasonic 50" plasma.
