My WER has been on three bikes (DR350, then RMX, and last son's RMX); about to go on a fourth (KX/KDX).
It's fine for the desert, especially enduros as it frees the upper bar area for timekeeping gear, and has a huge following amongst east-coast woods riders.
I have a GPR, and I like it in the desert better (more resistance than stock WER and better for higher-speed riding), but not in the mountains due to the return-to-center resistance. For that reason I'm looking for a trade with someone who has a Scott's or WER.
I've yet to try a Scott's on my rides.
Each have their plusses and minuses.
GPR: free rebuilds forever, but in action resists both aways and return to center (some like it, others don't). GPR is growing in popularity, especially with the desert crowd.
The WER is a space saver; no special top-clamp mounting required, but does require some headlight shroud/number plate thrimmings and mounting to fit, requires regular maintenance, and wear parts replacements. Targeted for the woods rider?
Scott's has advanced circuitry, but does cost for maintenance like the WER; longtime popular with desert racers.