We’ve tested three different Power Meters:
Of the three, our experience with Quarq is by far the best.
I started with a Stages Power Meter. We had the early version. The battery door let in water and the accuracy was not good. We upgraded the battery door, but the power meter kept bombing out after riding in the rain or washing the bike. I tested the first version of the Vector Power Pedals. They were inaccurate compared to the tacx neo. I had them serviced multiple times. They were torqued down correctly and I upgraded the firmware multiple times. I rode with 2 power meters for about a year inside (Tacx Neo and the Vectors) and finally gave up on the vectors. The Quarq is consistently within a watt or two of the Tacx Neo. They never seem to get damaged from water (rain / washing) and they stay calibrated as the temp changes. I’ve never “tested” that last statement, but after calibrating the Quarq it seems to hold the calibration as the temp changes based on perceived exertion.