For those looking at or for the remaining LE643U sets around....or primarily for some FYI to those already with them since they seem to be discontinued now....here are some interesting tidbits I discovered while messing with my problematic LC-65LE643U I picked up recently.
As it turns out, these are not true Sharp sets. They are 3rd party licensed sets like some of their low end smaller ones at best buy and the like. Both the LC-55LE643U and LC-65LE643U are both made by AmTRAN Video Corporation....and at least with the 65" model, uses an AUO T650HVN05.5 panel which is a 10bit AMVA3 panel. Full panel specs are here: http://www.panelook.com/T650HVN05.5%...iew_23780.html
Also interesting to note, is that these 2 models are shared with the respective sized JVC Emerald series sets (EM65FTR and EM55FTR). They are not quite 100% identical however. While exactly the same externally, panel wise, etc...the main board and tcon is slightly different. I mean they are the same boards shape/mount/port/etc wise and fully interchangeable in that sense, the actual component configuration with the chips and all is slightly different. Most noteable is the Sharp version has 2 LVDS cables going between the main board and tcon, and of course 2 from the tcon to the panel, but the JVC version uses one LVDS cable between the main board and tcon and the standard 2 from the tcon to the panel. All else it the same. Despite that slight configuration difference, the Sharp and JVC versions use the same firmware (which is how I stumbled upon that and started looking deeper in the first place), so I don't know what that configuration difference amounts to in terms of features or processing.
Besides gee whiz info, this gives you some options when the set is out of warranty and you want to try repairing it vs trashing it. Unlike most brands, you can buy JVC parts from their website, and actually reasonably priced in most cases. For example for these sets, the mainboard is $89 and tcon about $30. If you had one of those parts go out on your Sharp, you could theoreticly pick up both of those (note the above configuration difference) and turn your set into the JVC version...and of course the power board and other parts should be straight up interchangeable.
Also, I have seen various places, people comparing input lag and such to other Sharp models like the 650's and the like. Given this info, these models should have nothing in common with true sharp models, and should be nearly identical to the JVC Emerald FTR models, so keep that in mind.
As far as the problems I am having with mine, that stuff is here: Help! Bright scenes are good, dark scenes TERRIBLE blocky mess