That's the Android TV so for the dollar it looks like the better deal. Now the naysayers of UHD 4K in the links to follow neglected to tell if the hookup was over HDMI. That's limited to 30Hz as noted widely. There's a lot to learn on these things. However for the buck I'd nod to the android tv.
http://www.hdtvtest.co.uk/news/sony-youview-201502064005.htm
https://www.avforums.com/threads/sony-kd-x830-c-owners-thread.1962965/
For me I'd supply the set with the usual 1080p and let it upscale.
Hi there. I'm looking to buy a new tv. I was looking at sony. First model is sony x900b "55". And the other one is sony kdx8307 "49",,,,the two of them are 4k. I can get the x900 for 1600€ which is down the price from 2400€ Because it's last year model. and the x8307 for 1200€. I'm wondering which is the best tv all round. Thank u

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