Review on SKYRC GSM-015 GPS Speed Meter - High Precision GNSS Tester for RC Drones, FPV Multirotor, Quadcopter, Airplane & Helicopter by Michael Altayeb

I think a 3 star rating for this product is fair value in the short time I've had it. It came on time as advertised thanks to AMAZON 2 days. But when I opened the package, the item appeared to have been opened before. Can't say it has been used but the packaging showed all the signs of previous treatment. My biggest gripe with this, and one of the main reasons for returning, is the touted "software" and available firmware upgrade option. INDEED? You can download software for both MAC and Windows boxes from the manufacturer's website. That is not true. This is a Windows only program and I have a MAC. When I got the program to open it crashed immediately so I tried installing it on a windows computer where the program would recognize the device but the DEVICE didn't recognize the software so I couldn't make any adjustments or even could transfer data. All I wanted to do was increase the refresh rate from the default 1Hz to 10Hz per second for a bit more accuracy. This shouldn't have happened no matter how hard I tried. FAIL When enabled, satellites in the open sky were found very quickly. This gave me a walk speed in the driveway that was literally the limit for 'testing', so I have no reason to believe it won't perform as advertised.