After using it for a number of months now, in about six different vehicles, I'm impressed.
It does everything it's advertised to do, and once set up, you can set and forget it.
It does, however, have a few faults. It's quite difficult to set up, and the lock feature is a bit obscure in terms of calibration. The instruction manual reads like a bad translation from Urdu.
It will unexpectedly let go of the windscreen, and fall down. It's sturdy enough to withstand this, but it is disconcerting.
I've posted this video to give you an idea of how it works at night.
Set up this way, it shows GPS readings which (providing you were doing the right thing) could be useful in court.
This segment was taken between Esk and Gatton, into a setting sun.
The vehicle was a Commodore ute.
Here's a link to the instruction manual, if you're interested.