I have a customer who was looking at putting a TV lift cabinet in his hearth room where the main surround sound system is being installed. The cost of a TV lift, as he found, was quite expensive.
There's a few other reasons I don't see TV lifts being used very often besides the prohibitive cost. For one, interior designers today are comfortable with a TV in sight. It used to be they'd do anything and everything to hide it. Once flat panels came along they became a more tolerable intrusion on the designers plans.
But what's an interior designer to think of the front end of a '69 Camaro used as a TV lift. Someone has built just that. It looks like a car came crashing through the wall. Here's the story from TV Lift Cabinet Blog, The 1969 Camaro RS/SS TV Lift Project.
If you have a question or if I may be of service email me at email@example.com