Don't know of a specific company to test them, but I use a GPS in my tuning and it is very accurate. The only problem I have is a few milliseconds latency.
I checked it against a few roadside signals that uses radar that flashes speed and they were both identical.
If you don't have a GPS, but do have an Android phone, there is an application called "Ulysses" (free download) that some have tested against a GPS for accuracy and their findings were acceptable.
|