No VT25 but it was my 42G25 that showed me that I could have all that I wanted but could never get from LCD. There is a huge improvement in black, shadow detail and brightness.
I did a quick look up of Chad B's reviews to find the mll for all four sets- VT25: .005 G25: .0083 VT50: .002 GT50: .005
I guess that does say a lot -eh? The thing is that the panels, for this year's models, are new and so is the filter for the VT. I believe it's the filter, that while slightly better at rejecting reflections, produces a slightly dimmer (less vibrant ?) image than the GT50. I guess this is why I don't feel compelled to have the GT calibrated but really did with the VT and I don't know whether calibration can over come the filter's effect or not. I feel that calibration will result in getting better shadow detail that would meet or exceed the GT, but that opinion is not supported in anything solid that I can point you to. Actually, the problems that people on the VT50 settings thread are experiencing, make me wonder if exceeding the shadow quality that the GT50 provides is possible. This is why, had I kept the VT, I would have only been satisfied if D-Nice calibrated my set.