Talkiet:
I finally narrowed it down to a Panasonic 54V series (2d) or 50VT (3d) and after seeing them both side by side went for the 50VT based on the fact it's a little newer and everything I have read seems to indicate 3d TVs do a better job of 2d as well.
Unfortunately the VT has problems with 50Hz signals. Panasonic in the UK have stated that the TV is optimised for 3D/blu-ray and that there will be no updates to address the 50Hz problems.
http://www.avforums.com/forums/13261073-post715.html
Whether or not this will bother you, will ultimately come down to the type of programing you watch. If you watch lots of broadcast sports, then you'll likely have less satisfaction than if you watch lots of blu-rays and gaming.
The 54" V10 would have had its own set of problems to deal with (namely black level depreciation).
There is no perfect TV unfortnately.