I know this is a significant bump but I felt I should make a point I happened to make on another forum a day or so ago on the subject.
It was actually a thread where someone was asking about advice he had received to rip out some drywall to affix a plywood piece to his metal studs so that he could securely mount his tilt and swivel Flat Panel TV mount to the wall.
A big 50" Flat Panel. Weighing a massive........12kg [big grin]
I made the point that received wisdom on flat panel wall mounting is hopelessly out of date even if only 3 or 4 years old. Up to quite recently Plasmas were the flat panel kings. Big 5" thick 50" glass fronted screens that weighed 50kg. 3-4" thick 42 inchers that weighed 40kg etc. Back then, if you wanted a plasma any thinner or lighter meant buying the uber expensive flagship model.
In the last few years things have changed to the point that Panasonic the Plasma leaders shut down production and don't even make plasmas any more. LED/OLED LCD's are now the Flat panels of choice. These things, even the base models are now mere centimeters thick and weigh a fraction of what the plasmas used to back in the day.
What does this mean? It means that all the old mounting advice still parrotted today is out of date. The guy in that other thread can likely mount his 12kg 50" Flat panel and mount to his studs with 2x 2" screws [big grin] Exaggerating a little but you get my point.
I also explained in that thread about how I was keeping this in mind for a project that I have on the back burner. ie. Some beds with 40" flat panels mounted inside the footboard that rise out of the footboard on TV lifts. You've been able to buy something like that for years but you'd be talkin 5 grand + 1. because the 5" thick flat panels of the day required a separate substantial piece of furniture to house them at the end of the bed and 2. You needed a $1,500 linear actuator TV lift like that linked in the OP here to lift the 150LB TV!!!
Just googled a random 2015 Samsung 50" LED/OLED Tv......2" thick and 28LB !! 40" was 1.9" thick and 17LB
It doesn't take a $1,500 TV lift to lift a modern Flat Panel.
I'd wager that when I get around to building the footboards with TV lifts, the Wood, the material to make a scissors lift mechanism and small motor and arduino controller or somesuch capable of lifting a mere 17LB would all come to less than $300.
So what I would say is don't be automatically clicking the BUY button on even the $500 TV lift systems never mind the $1,500 dollar ones before you do some more research.