I have three digital tire gauges. 1 is a Slime, 1 a no-name brand, and the third is a RoadGear. All three read a different pressure on the same tire. For some reason, I trust the RoadGear one, so I add 1/2 psi to the slime gauge's reading and subtract 1/2 psi from the no-name gauge's reading since the RoadGear always indicates right between the two.
I've always wondered if there's any way to find a truly accurate gauge.
Cheers,
Dan K.