I have the carb synchronizer from Brent with the mercury. I appreciate the accuracy of mercury, but I am sure it is more sensitive that the hard metal floats in the carb tune.
I also appreciate mercury in what it can do to our bodies.
I seal up the synchronizer every time I use it, and will not travel with it. Both kits travel well, but the mercury stays home in a safe, in an "away from people" place.
Ride Safe,
Dennis
