I haven't flown with it yet. I did install it and power it up. Works as advertised. It heats up and then turns off. The LED indicator on the panel is very cool.
Drawbacks: had to elongate the holes in my Gretz mount for the pitot to fit, running an extra 3 conductor out the wing (optional for LED indicator), and Gretz's non-warranty (it's only good until you hook up the pitot to your plane).
I can give a flying report in a few months.
Dave