I have a Smart TV with a slow interface.
Sounds like an Amazon Firestick is effectively a SmartTV on a stick and is therefore a cheap effective way to make my TV usable.
It seems generally agreed that it's worth running Kodi on the Firestick.
What exactly does Kodi add to the functionality of the Firestick?
Isn't it so you can watch pirate movies?
Well, it's xbmc. So you I guess it means you can play all your ripped dvds that you've put onto your home fileserver.
You could also use a RaspberryPi, and I think you could also use Plex on a Roku.
I've been thinking about this today for our 2nd TV. I have been using an AppleTV2 with kodi/xbmc installed for about 4 years and it's great - only installed the Genesis app yesterday though .... wow!
Quite handy seeing as MrsSB just cut the satellite cable while gardening!
For the money I think I'll get another Raspberry Pi though (my 4th) as you can then load tons of movies onto it as well as have it do many other things