Anyone have decent experience with sideloading apps like NBC Live Extra, WatchESPN, etc?

I don't have cable, and I use these apps to watch sporting events like Premier League soccer. The apps on tablets and phones work fantastically, with minimal buffer times and few stutters, but casting the screen to my Chromecast sucks, and there really isn't any way around that.

With that said, I assume running those apps directly on a device like the Nexus Player would result in a similar experience to that on the tablet or phone. I know these apps aren't designed for Android TV, but I've heard of some workarounds (Bluetooth mouse provides cursor on the screen for clicking buttons etc)

Has anyone used these streaming apps on the Nexus Player? If so, how was the performance?