I have a data cap, so it wouldn't have been viable for me. I did try Amazon Luna when I got a trial invite just to see what it was like, and it was mostly okay, but there were times where the graphics would glitch a little, and there was a slight delay. Both of which are byproducts of streaming. Those annoy me enough to never subscribe even if I didn't have a data cap.
Twitch: https://www.twitch.tv/kid_prodigy23