I own two Samsung DLP RPTVs. One is a slightly older HLN617W that is the display in my HT. The other is the newer HLP5063 in my bedroom. I like both very very much, have had no trouble with either, and can recommend Samsung highly.
I did a lot of comparisons in making the decision to go with the HLN617W. The HLP5063 purchase was not based on comparisons as I was fully satisfied with Samsung, and had been tracking the design improvements at avs forum.
One comment is I believe the digiupdate page was the one that Arun Gupta ran, but unfortunately Arun was killed riding his bike and the page is no longer up to date. I second the recommendation to go to avs forum to get the latest information.
Just as no technology is perfect; e.g., some see rainbows although I never have, I expect no one brand is perfect, so you need to weigh the pros and cons of each. Samsung was the only game in town when I was doing my comparisons (primarily Samsung DLP to Sony GWIII), so I cannot comment on other DLP brands.
If DVD viewing is a priority, then one thing I would look for is the ability to accept a 720p feed via either DVI or HDMI, and the ability to display that without any intervening processing, so you can take advantage of an upconverting DVD player. The Samsungs can do this. RCA has/had a model that could not. It downconverted to 480i/480p and then rescaled to the native DLP resolution of 720p - needless extra processing.
I would appreciate feedback on any comparisons you do between different brands of DLP RPTV.
Thanks
Bruce