Product review (2 stars): It Works -But Not Recommended For most Users.
The price is very good, but there are a couple of major shortcomings.  First of all, the temperature is C not F.  The U.S.. Government went metric in 1868, but everybody still uses Fahrenheit.
The other problem is that it takes forever - about 7 weeks - to arrive.
The unit is fairly chunky, and there's no good way to mount it.  I would recommend double-stick foam tape...