I have not really heard abything about JVC TV's, so I would have to go with the Sharp. Also, I'm guessing you didn't notice the Dynamic contrast ratio of 10,000 to 1. That is a really big step up from the JVC.
Personally, I prefer Samsung TVs. They have great tech specs and everyone that I know that has one, loves it. Here are two that I would recommend.
Newegg.com - SAMSUNG 32" 1080p LCD HDTV - LN32A550
Newegg.com - SAMSUNG 40" 1080p LCD HDTV - LNT4061F