Any reason you are looking at only Samsung? LG has a good option in that price range, 55LM7600. ES6500 is comparable but not the other two.
3D, as I see, is mainly for kids / guests. Or may be for some Blu-Rays that are authored properly like Avatar 3D, which looks fantastic on LG. I am sure Samsung would be good as well (I had a top end Samsung plasma and was pleased with the quality) but passive 3D makes a 2-hr long movie watchable. The reason I'd suggest going for a 3D TV is that these also have excellent 2D picture, usually better than the pure 2D models.
There are tons of calibration settings on LG, I especially like the RGB filters. The light bleeding could be an issue for some sets and you may have to exchange a few times. I'll decide whether to exchange after the calibration. Some smart apps are not bad, the remote is also useful for apps though needs a day or 2 to get used to it.
The only reason I'd look at ES6500 is for the 60" option though the price is too high at present and LG 60LM7200 is possibly a better buy.