I must tell you that Video quality of LG 3D TV is just awesome. When you watch 3D content it feels better than Theatres believe me. To experience this you can take a 3D demo at any LG store or TV store from where you are going to purchase.
Sound quality is great. You won’t need external speakers as TV sound is more than enough and even it has surround sound.
You won’t get such an experience in any other brand. I have invested a whole year in research of a good 3d tv. You must go for it guys as you won’t be disappointed.
Service of LG is also good. Customer support helps out most of your problems during a phone call and if there is a need their representative will visit at your place.