For me, it was a matter of tradeoffs. At first, I was very interested in a CRT RPTV but I preferred LCD RPTV for the low maintenance, no burn-in risk, and wide viewing angle. The newer Sony 50" GWIII will debut in a few weeks and it will be less expensive than the current crop of GWII sets. If I were buying today, I would take a serious look at the new Panasonic LCD RP and the upcoming GWIIIs.
To help you decide on your budget, ask yourself how long it will be before you upgrade from this next set. I plan on upgrading in 5 years or so and that kept me from spending more.
A 50" GWII was the right performance for price for me. I'm finishing my 2nd month with this set and I am having a blast with it.