We should be more specific. The 505HD is the 2d generation Pioneer. It has been superseded by the PRO1000HD. These are the "consumer" models, FCC class B certified. the 1000HD is also styled as a Pioneer Elite model with a large, black frame that many folks hate but a few love, altho the frame is removeable without voiding the warranty. it has a 2-year warranty and comes with a table stand.
The 2d generation "industrial" model, the 502MX, has been superseded by the new 503CMX. This model, almost identical to the Pro1000HD, has a silver frame, an acrylic front (the 1000HD uses glass and is a few pounds heavier) and a 1-year warranty, and two odd-looking "feet" instead of a pedestal stand (which can be bought separately). The plasma substrates are identical.
Both models use a "video card" approach; both have what looks very much like a PCI card. The 1000HD comes with a card installed, which has various connections on it (s-video, component). The 503CMX comes without a card, but most vendors are offering the companion card (PDA5002) as a bundle and it's a few hundred bucks extra. this card contains s-video, component and DVI-D inputs. Forum members have inserted the 5002 card into the pro1000HD and it appears to work, altho the manual cautions against removing cards once installed.
The picture quality of these units is a significant step up from the 505HD and 502MX. See the detailed review in the current Perfect Vision or at Pete Putnam's site,
www.projectorexpert.com.
Dell has been offering the 503CMX via it's 'small business sale' for $8450 or so, plus the cost of the card. the Pro1000HD sells through video dealers and is priced higher.
There are numerous threads with pictures and lots more details. Please search the forum.
cheers