Is the Sony A90K worth it over the A80K?

The A90K adds a brighter panel and better processing for a price premium. If you watch in a bright room or game often, the A90K is the stronger pick; in a dark room the A80K covers most of the same ground for less.

Is 48 inches too small for a living room?

For seats 6 to 8 feet away it works well. Beyond about 9 feet, most viewers will want a 55-inch or larger set.

Does it support 4K 120 Hz and VRR for PS5 and Xbox Series X?

Yes. It has HDMI 2.1 inputs with 4K at 120 Hz and VRR, so current consoles run at their higher frame rates.

The TV, its stand, the remote, batteries and a power cable. No HDMI cable is included, so buy one for each device you connect.

Is burn-in a concern on this OLED?

It can happen with static logos, tickers or desktop taskbars left on for hours daily. Vary content and use the screen-off timer if you watch a lot of news channels.