I am in the same situation -- only I'm researching for a 50" or larger set. I already own a 37" Sharp Aquos, which I like except for a few nagging issues. I thought the Sharp had the best picture a year ago, except when I looked at the comparable Sony. That, of course, was based on no tweaked settings, as viewed in several big Retail stores.
Right now, my biggest concern as I've learned more here at the AVS Forums is that most sets fail horribly to display the full resolution they are capable of -- up to 50% of the stated resolution. This is based on tests conducted and reported at Home Theater Magazine on both 2005 and 2006 models. What this means is they cannot correctly display a true 1080i image (or 720p image, if that is their top resolution).
In both years, however, they determined that the sets which did pass these tests consistently were Pioneer (premium dollars), JVC, Hitachi and Toshiba. Not all sets from a given manufacturer that they tested passed, however.
The tests were labeled as "Are You Getting All the HDTV Resolution You Expected?, by Gary Merson (search on Google -- unless you want to avoid being really disheartened)).
So... if you do not plan to buy a decent A/V Receiver, I'd look for a JVC, Hitachi or Toshiba in my size and price range. I would then search for Reviews online as to the best image quality. And I'd probably stop worrying about any nitpicking here at AVS -- unless the issue reported was important to me.
Some report issues of problems with a specific Blu-Ray DVD hook-up, as an example. If I'm not hooking up to that specific device, why worry? Some say this or that unit has trouble with the PS3 -- are you going to buy one? And so on.
If you do NOT plan on buying an A/V Receiver or DVD Player with a decent video processor, I will go out on a big shaking limb and suggest the JVC, Hitachi, and Toshiba options may be a good choice. The units you list above may be acceptable choices, too -- unless you really must avoid green problems, etc. None of these three were listed on the tests I mentioned. Sharp, however, failed in all of them to some degree (read the 2006 test to see where).
The main reason that the test mentioned above are very important to me is because I'm trying to avoid buying unnecessary equipment to do repetitive tasks. I may not need a Receiver if the TV can process the signal well. But many of them cannot -- and that truly frustrates me.