What a stupid title. As if anybody's buying smart devices in the hope they'll be worth more someday.
My on topic advice: if you rely on your smart TV to get to your content, you're going to have a bad time. Get a small computer instead, and treat your "smart" TV as a monitor, nothing more.
I did get myself an nvidia shield last year, and after switching out the stock launcher for something that doesn't show ads (and better yet, launches straight into plex at boot), I couldn't be happier.