Consider the technology first that which brand is providing the best 3d tech, features of 3d tv like these days some manufacturer is having the internet options in its 3d tv.
Size should be consider according to your placing area.
And at the end compare the price of different brands to each other.
Couple of days back my friend asked the same from me as he is going to buy a 3d tv soon.
I advised him to visit any 3d tv store before finalizing to compare.
But is there any way through which you and I can help him out in making his decision for 3d tv?
Suggest some point of consideration on how to buy a 3d tv?