I saw you switched from the 8500 to the VT. Congrats on your pick up. I saw your impressions and mine are basically identical to yours for my ZT. In regards to the vertical banding mine is basically the same as well. I get vertical bands that are very very very faint on some grays on the left side of the display. What I did was switched out the standard 12 color slides to the 120 color slides and I was able to see 1-2 more vertical bands on the right side. All at higher IRE. About 2-3 steps from white on some blues and purple/pinkish tones. Whats funny is much like yours you have to actually look for it. And even then when you try to see it at times it just gets lost. You almost have to focus on it in a certain way to see it.
Also I also felt that THX Bright gets pretty damn bright so glad I'm not the only one, but at the same time my last display was set at 33.4 ftL
Also thanks for your comment on the 8500 "sharpness" as I had a feeling it was doing some sort of edge enhancement. Do you know if it had any kind of motion smoother or frame correction that couldn't be disabled?
I asked David Mackenzie on HDJ about the panel brightness since they stated how much like the 2011 models the 2013's were and he said they had to calibrate at MID panel brightness because you get a S type curve. So I assume much like the 2011's it will start low, spike, drop, and spike again.
I swore Panasonic released a fix though later on that corrected that and allowed for panel brightness high. Also I think there was a work around that involved the increase in magenta when calibrating. I'll have to check my emails on that one though.
LivingRoom: XBR-65X900B / Oppo BDP103D / Pioneer Elite SC35 / REL T7 / HDP2500 / Def Tech Mythos Ones x 4, Eight, 2x Gem XL / PS4 / Xbox One / Wii U
Bedroom: 65ZT60 / Oppo BDP93 / Apple TV / PS3
Office: KRP-500M / Xbox 360