infintity-it:
I was impressed by the simplicity of the installation. I have used the GAU-1000 (which is the lower priced version that doesn't take other data, like engine data and can be temporarily mounted nearly anywhere - their other model requires a permanent installation). Runs for up to three hours on internal battery and can be powered with 12v adapter.
Setup was easy, and calibration was also easy (I nearly said straightforward, but that would be misleading - calibration requires two 360° turns on the ground…).
It sits there and quietly gives attitude in pitch and roll, heading, pitch and roll rates and accelerations and speed (obviously groundspeed).
Software was easy to use for post-flight processing, and you can export the data to Excel very easily.
I've used in in a helicopter and also on a car and will be using it on trucks for coast-down testing. Impressive stuff and very inexpensive.