I just purchased this new unit. I still have concerns over DLP technology and went ahead and bought a CRT unit. My questions is this, is it worth it to upgrade to a HDMI DVD player with this unit, since it isn't fixed pixel, will the HDMI DVD player make that much of a difference as far as picture quality?
It depends on which player you get. If you have a high quality progressive scan player connected with RGB component cables, then you likely will not notice that much if any of a difference. A friend bought the Toshiba DVD upconvert player for his Hitachi 57" CRT and he raves about the picture quality of his DVD's. I have the exact same tv as him, and I have the Pioneer Elite DV-45A progressive scan player, and the picture quality for DVD's is second to none.
Bottom line, if I was in need of a player, then I would get an upconvert model. If you do end up getting one, set the output for 1080i. That is what RPCRT's are scanned at.