I can't comment on any of the specific models you mentioned. I can tell you this, take the manufacturer's specs with a pinch of salt. 4ms response time sounds great but you should check out the models you are interested in while playing the content you intend to watch.
One thing to keep in mind, HDTV broadcast stations have a wide variety of broadcast quality. I'm a football fan and I've noticed that some over-the-air stations are better than others. My TV is not high-end and I can tell the difference. The games on Fox were better than the locally broadcast games during the pre-season.
If you plan to use your set for HD-DVD or Blu-Ray or upscaled SD-DVD discs, you should audition the TV with those in mind.