I must respond to Sogood51's comment regarding the Infocus X-1, as stating it "blows RPTV out of the water!"
I used to temporarily own the X1, and that would be rather subjective. Actually, rainbows and lack of good black level, not to mention DEFINITE EYE STRAIN, would keep me from ever making that statement! (and I'm rather subjective and open to view's). No projector I've seen yet under $5k has as good of a black level and as accurate of a picture potential as a properly calibrated (good quality) CRT based RPTV!!! And still, I'm a huge front projector fan and advocate!...gotta love the large screen image!
Still, let's be reasonable, there are some excellent RPTV's out there at 60". The Pioneers, Mits's (not as 3d as some), Tosh's, Sony's and many others offer some superb, even world class picture potentials at 60"! For all practical purposes, doing 1080i or 480P at this size is adequate. some will do 720P, even better.
Still I would say your choices arn't as critical as you're inquiring for! A PROPERLY CALIBRATED QUALITY tv is what you're after! (light control in room is a huge plus as well) calibrated right, there are a ton of simply stellar RPTV images to be had from many! I wouldn't limit your thinking to the thought that you need to find "that one special unit!"..seriously!
Find one that has a good rep, good reviews in the Hifi mag's, and get it calibrated! You'll never look back.
The only real thought you might have is whether or not you might have considered a front projector and separate screen set up for that money!!! a $5K faroudja DLP and screen would potentially get you an image that overall rivals what you might get from a smaller RPTV for overall impact! But, that's subjective. I do find that once you take that plunge, you'll never likely want to go back! This stuff's getting better and cheeper all the time!
Infact, that said, I wouldn't pay $4k for an RPTV at this point, as you can get more than superb for around $2500 at this size new! Again, a properly calibrated "decent RPTV" will look worlds better than an improperly calibrated world class Elite, XBR, or whatever TV! That's the truth.
Good luck