Years ago I was faced with the same dilemma. We don't watch a lot of tv when camping. When we are on an extended trip we do. Here is the issue I focused on. If you use a
12V tv then it is going to draw down your batteries. When that happens, what do you do? You will have to crank up a generator to recharge your batteries. If you are in a full hook up site a
12v tv is a waste of money. When we want to watch tv we crank up the generator. Like I said, we don't watch much tv so it is no issue having to run our generator.
I suppose it will depend on how dependent you are on your tv. If you don't want to bother you neighbors when you watch late ino the night, then get a 12 v . You will have to charge up the house batteries in the morning though. This is an electricity thing. You will either have to pay now or pay later. It is up to you.