Every week I see the Pioneer Kuro non-Elite, Elite, and Panny PZ750 all side by side. To be honest there's about a 25% difference each step up you take...but that's my opinion. Keep in mind, once you have one of these in your home, you'll have nothing to compare it to...better or worse, so it'll look awesome regardless!
Where do you see these sets at?
25% difference...Pioneer Elite > Kuro > PZ750?
Anyways, I do agree with you. I was looking at 50" PDP-5080's and the PZ700U's. Because of the additional features, and the price, I had settled on the PZ700U. But the picture quality was very close, but PZ700U still a little better. The PDP-5080, even though it's 720p, was blowing away most of the 1080p HDTV's on the market.
Now fast forward to PDP-6010 vs PZ700U. The 6010 is a 1080p, 6months+ newer, and I believe (though I may be wrong) is built on similar technology as the PDP-5080. PDP-6010 > PZ700U.
From what I've seen in a showroom at a couple HT based stores...not the BB or CC crap. Setup using dedicated blu-ray players and connected via HDMI, the PDP-6010 > PZ7xx line.
I don't claim to be an expert, and I did not have any DVD's on me to run a full suite of tests. this is just my .02 from reading reviews, digging through forums, and seeing them in person.
Even though it's been said...get which ever is in your price range. If I could afford it, and I was looking to get a TV, I'd get the PDP-6010.