I bought one a couple of months ago and they work fine and dandy. I just put Android USB TV Stick into fleabay and got loads of results. I eventually went fro one which was sold by the BT Shop but it looks as though they don't sell them any more.
When I got it, I played with it for a day or so but at the moment it is gathering dust while I find a proper use for it which will most likely be a Media Server. I've got a Raspberry Pi acting as a Media Server at the moment but it is very temperamental to say the least.
The USB stick works perfectly fine with a wired keyboard and mouse. I have not experimented with a wireless option but I'm sure it will work out of the box.
Getting on-line was a doddle to connect to my wireless router.
You can either pay many hundreds of pounds on a Smart TV or you can pay £20-£40 on an Android stick and achieve the exact same results.
From my personal experience, these little sticks work perfectly fine.