My LED is 3D and it's great for gaming. Sole reason though is because I have 240 hz, highest refresh rates on LED TV possible, or at least when I bought it, making it a better TV for gaming and sports rather than just casual watching. However, I have played on 3D TVs before with lower refresh rates and yea, they were complete garbage. Either way, it still boils down to refresh rates.
the only way to stop the input lag on mine was to put the channel input to pc mode dont have a clue why someone just adviced it on a forum. it worked though