No direct experience- but the general sentiment over in the gaming forum is that the higher end samsungs have problems with lag. One of the main reasons I've avoided samsung panels as I'm a gamer.
A quick "pulse" of user comments reveals panasonic, sharp and sony to be displays with little to no input lag.
What to do if you find yourself stuck with no hope of rescue:
Consider yourself lucky that life has been good to you so far. Alternatively, if life hasn't been good to you so far, which given your present circumstances seems to be more likely, consider yourself lucky that it won't be troubling you much longer...
-- Excerpt from the Hitchhiker's Guide to the Galaxy.