Visually it looks very nice with the chrome ring and the analog optics.
The radio transmission funktiniert but completely unreliable, despite fresh batteries.
The range is somewhere stated at 40cm and is even lower in reality.
In order ever received was there, I had the speedometer on the handlebar to turn down, so it was profitable at best only for the total kilometers of track.
The speedometer is not water-sealed, ran several times brimming with me.
In addition, systemic shortcomings: So radio speedometers can not be activated automatically. Say: It is usually already driven a few kilometers before one can think that you still have to turn on the speedometer.
My attitude now is: Hands off cheap radio speedos!