Actually, that's a serious question. I'm looking for a box to recommend to a friend who's going to cut the cord. I think the Nvidia Shield will be better for them due to being real android tv, and because I have one and know the Android TV ecosystem better...
It looks like FireTV still doesn't have an easy way to install Kodi from the appstore, but requires that it be side-loaded.
And it looks like the Youtube app in the amazon app store is written by Amazon. The icon makes it look not not legit..