We have just got a 3D TV although it was brought with 4k in mind and we've used 3D a couple of times so far, content.picture seems good only thing is those glasses, the bloody things make me tired within half hour
and I fall asleep. We have active not passive, don't know if I would fair any better with those types but I ain't forking out for another new TV.
From what I have read, 4k is the push for manufacturers now as 3D didn't rely take off at all.