It's a fun, easy and cheap way to mine. It's very quiet and low power. They use chips off newer machines so they are efficient. You can mine in a pool and get tiny amounts of sats, or you can solo mine. If your Bitaxe hits a block then you get the full block reward, so it's like a one time purchase lottery ticket that keeps trying to win for the life of the Bitaxe.
I got one about 6mo ago and I like it. It's fun to know I might hit a block.