I'm not really found of any of these stick devices because they fail at one thing i want.
The ability to stream content I have on my computer to my tv.
Chromecast is all all about streaming youtube... go to other sites and you'll find them blocked..
Have avi, mov's or other video files on your pc... forget about streaming them.
The firestick seems to be the most flexible as it can be flashed with other software.
Roku... well if you have a smart tv.. haved a roku is kind of redundant.
After spending months fighting with these devices... I returned them all and build a HTPC...
it lets me run what I want when I want without all the blockages and hassles..
That's isn't 100% true. While Chromecast does not have a native interface (hence it tanking some of the key categories) they're plenty of Android apps that let you cast content on a DLNA server on your local network to the device. My favorite right now is Localcast.
I prefer the Fire Stick, because of 2 apps...SET TV and Terrarioum TV which you can't get on the other 2 devices. Now I can watch any tvshow, thats ever came oiut I can watch over 500 HD channels, all the sports I can consume whenever they are on, PPV boxing or UFC, HBO, HBO west HBO East, Showtime, Cinemax, its mind boggling, I had people who had direct tv and cable see my setup with the fire stick, cancelled or lower their plans, most cancel it makes sense because set cost $20 a month for 3 devices.
The best one for Colombia, and maybe Latin America is the Chromecast. I recently bought a Roku and pretty much only Netflix and Youtube works, all other content is either blocked or unavailable. Fire stick is probably the same story (not willing to pay for it to make sure i´m right). With my 1st generation chromecast i can get HBO GO, Fox Premium and screen mirroring, as well as the other features I mentioned previously. My recommendation is to stick with chromecast if you don´t live in the US.