I really respect the operating systems a lot but the hardware rules too. I don't know what to choose LG for the quality of the pic (from what I have heard) but the weak web os or Toshiba 40L5550E which is the only available android TV in the store ?! Welp Edit: after reading through this sub reddit clearly I am on the wrong place but anyway feel free to drop suggestions Edit 2: glad I asked thank you for your all your responses...you know it will help me.
NO!
Would you buy a car because of it's audio system?
Buy a TV for what it's supposed to do: picture. Then use secondary factors, like inputs and other features as your next level of factors.
But don't take the OS into account at all. Why would you when you could easily replace it with an external source of the same thing for, at most, $150.
Buy a TV based on picture quality. You can then plug anything you want into it.
webOS is perfectly fine for changing volume and source inputs on a TV. It's also not that bad if you just want the basic Smart TV features. If you want more than that, stick with something with better hardware and the prospect of being supported for longer than the life of your TV.
Buy a set-top box running the Android TV operating system, or buy a competing product like a Roku. Those devices can be easily swapped out when better models are released. And you won't be stuck with inferior picture quality with an outdated TV OS.
Alot of comments here are about purchasing solely based on picture quality.
There are other factors too beside the screen itself.
Is 4K important to you and if so, make sure your TV is HDCP2.2 compliant for future proofing
If low latencey response important to you?
How many inputs does it have? How many of those are HDMI? Do one or more of those inputs offer high scan rates (the latter is important for sports broadcasts)? If you have 4 things to plug into your TV but your TV only has two inputs, then you're in for a bad time.
Are you a cordcutter? Does the TV have an ATSC antenna tuner?
That said, whether or not it has Android TV is the last thing I would ever look for. I see OEM adoption of Android TV the same way I see Android adoption on smartphones (fragmentation, infrequent updates, things like sideloading locked out, etc). Not to mention that for most android TVs, the hardware isn't even up to par to the nexus player.
Just get a shield or nexus player. Get a TV that meets all your other requirements.
Maybe others will disagree, but oh well. I have a Sony with Android TV. The OS is awesome, but not all that important IMHO. If you have a Chromecast, PlayStation, or Xbox, you can always use that to watch YouTube, Netflix, etc. I'd go with the better picture, because there isn't a way to get a better picture, but you can hack together the functionality of an Android TV with a $35 Chromecast.
I got an LG because I have a shield. No sense for me to have Android TV in the same room twice. I use apps from both pretty regularly. 4K video seems to perform better on the shield. Maybe more RAM or processing speed in the shield? The picture on the LG blows me away. I am not watching 4K all that often. 1080P is great though on it, especially games.
Edit: WebOS is actually not weak at all. Just depends which apps you think you will use most.
You can always buy a android tv box later. I would get a 2016 vizio though for the picture and the build in google cast.
A TV with a good picture will serve you well many years after any internal smart features are sadly out of date. The beauty of external Android TV devices is that you can replace them in a few years and keep your TV.
I bought Philips PUS6501 few days ago. I am very happy with this model, however Android TV doesn't seems to be mature yet, i hope it will keep growing. Anyway it's pretty cool to have Kodi builtin :)
The only thing that sucks in my opinion is lack of gigabit ethernet and rf/bluetooth remote :<
I wouldn't buy a TV based on OS. I would buy it based on hardware. Compare the sets on rtings.com