Got the XL2420T. The profile mode supplied for TF2 is sorta useless if you use dx8. The "Black eQualizer" thingy probably
isn't going to save you if your eyes are bad enough that you need it, but it does exactly what's advertised, that is, lighten dark areas without washing out bright areas, so it's handy enough if you, I dunno, have a really dark config or that picmip hack. Compare the light/dark areas in gully mid, for example.
Input lag is not noticeable. It's got some wacky feature where you can resize resolution, which came in handy when firing up Brood War. You can adjust the black equalizer from 0-15 real easily from the little remote they give you. It beeps on input but you can turn that off. The bezel is matte, not glossy. Only complaint is that the touch panel seems to light up at random if you place something near it, and the box has a scary black dude on it.
All in all, it's great but it's pricey. I'm new here, so I hope this helps somebody.