I recently bought an Amazon Fire TV Stick. I really like it. It's not a bad streaming device, although I would like it to have more integration with the various streaming services. As it can search Hulu through the voice interface, but it cannot search Netflix. In my personal opinion it would make it much better. The other major flaw is that the keyboard sucks. If it didn't have the voice search, it would be impossible to use. I hate clicking and scrolling to type, it stinks. Other than those flaws, I would have to say that I really like it. It has a real smooth interface for most uses. It supports casting from your cell phone for the major apps, so that's nice. The remote feels slick and well put together.
It turns out if you have more than a couple apps, the interface becomes kind of sluggish. I suspect that this is because quite a few of the apps that allow casting start a service at boot, and this starts to take a toll on it. This situation is made worse because there is no way to really uninstall apps from the FireTV. These problems do not change my opinion of the device as a nice media player, but it is inconvenient, so keep these problems in mind before buying.