I have a Hitachi 57S700 CRT RPTV(1080i), which I've enjoyed for 2 years, fantastic picture, especially running HD DVDS, my seating is app. 8' away.
I just bought a Sharp DT-500, I wanted a PJ that had a small offset( if fixed of course), and this fit the bill, LCDS will give you greater flexibilty in placement, but I prefer DLP.
I don't even have a real screen right now, I'm projecting onto a Brownish Gray wall, and while the pic isn't quite up to par in comparison to the 57" (blacks- can't beat CRT blacks), it looks fantastic.
The blacks are still VG, and if that RPTV you already have is a CRT, you will notice it, but it is NOT bad.
BTW none of the PJ's at this price point can display black like the CRT.
NONE.
This PJ throws a fantastic picture, at a VG cost right now, it is a short throw lens(I'm throwing about 100 or so at around 10').
Depending on what you want, and/or need out of a pj will determine what you end up with.
My goals were 110 or so @ 11+'(done), good blacks(done),small offset due to 7.5' ceilings(done), great picture at a reasonable cost (done).
There are some VG PJ's out there right now at a reasonable cost, I just happened to pick this one, and I'm happy.
'Tis a good time to be in the market for a reasonably priced HD PJ.
EDIT: BTW, I haven't setup my room yet, this is a tempoarary setup, and I have no SDE at 8' viewing distance,
Happy Hunting!!