When i pop back home to see the parents i use their 40" plasma and its excellent. Never had any issues - no screen burn or slow response time/input lag or otherwise.
Guessing your tv is too small for plasma (which has a good response rate as standard) so its led i guess? Dont know about the response time on your tv but that's not important unless you game. If its fine watching sports on it then it will be fine for gaming.
I forgot about input lag, lol. Yeah it can be quite bad on some TVs anything bellow 30ms is ok but anything over will be bad. If you have a game mode on your TV use that and turn any special features like truemotion off, that will lower the input lag quite a bit.
Id say 30ms is too high for gaming, not sure how much it is reduced using those settings.
If I've got this right then its quite simple to work out what response time you need on a screen, you divide 1 second by the fps you expect.
So 60fps requires (1/60=0.0166667) = 16ms response. However if you exceed 60 fps you can get screen smearing so you really need greater response.
8ms response is good for 125fps
5ms gets you 200fps. You can go lower but who games over 200fps? Better to choose contrast/light output (cd/m2) or other things like features and design.
Thing is, if you get too slow a response time then you get screen smear and waste the performance of your pc...but going below 5ms in unnecessary imo.
M&P