I have posted this in other threads, but since you asked...
I have had the Amazon Recast for about 9 months. It has 4 OTA tuners, a 1TB hard drive that can hold 150 hours of video, and a free program guide included in the price. I am very happy with it. It is very reliable. It has never missed a recording in the 9 months that I have owned it.
On the downside, you need an Amazon Fire TV device to use it (not so bad since the Fire TV device also has the Dish Anywhere app, and that works pretty well). Also, the Fire TV device and the Recast DVR have to be on the same network. That means that when you are away from home, you can only watch your Amazon DVR by using Amazon's Fire TV app. The Fire TV app is available on iphones, ipads, and other Amazon devices that support the Fire TV app, however it is not available on Amazon's own Fire TV. This is the major thing that I do not like, but it is not a deal breaker for me.
The Recast has allowed me to drop the local channels from my Dish package and save $12 a month. Also, I no longer care if Dish has a dispute with with one of my local stations. (In the past, I have lost FOX, CBS, and ABC while Dish negotiated a new contract).
EDIT: I should also mention that Amazon puts the Recast on sale quite often. I was able to buy the 4 tuner version for $179.99 ($100 off list price).