I have a 42" LG LED......i had tried mp4 & avi when it was new & it worked fine. Now the thing is - i have connected this PC of mine to the TV.......so i didnt bother for checking which other formats were supported!!But regarding PQ, i think LG is really good......actually i think thats coz of "LED" factor. When i got this 1 in Feb 2010, there were 2 players oly who sold LED - LG & Samsung......Samsung 40" was about 20% costlier than LG 42".......So, my advice would be compare such differentials before buying & as far as possible, move towards newer technology......instead of LCD/Plasma, get LED.!) When u see the 3 side by side, ur eyes will automatically be impressed the most by LED 2) Its lot slimmer 3) Has a really wide viewing angle - practically 178 degrees - still there wont be any change in colours. 178 because the natural line of sight prevents u from seeing a 2D thing at an angle of 180 degrees.4) It is very light on ur electricity bill as well.Pricing difference between LCD & LED is quite a bit.....esp for 40+ inches, but its worth a spend......