+1 on the dial gauges but I have moved on to Accutire to keep in the vehicles.
I have a Radio Shack digital gauge that sits on my workbench. It agrees with a friends Accutire I borrowed.
I have an Accu-gauge dial gauge I compare to the Rad Shack once a year or so.
I do routine tire checks with the dial gauge.
I dropped the dial gauge once and had to re-calibrate it.
I have the little tool to pop off the needle, from my years working in a metrology lab.
It currently reads 1 pound over at 32PSI (for car tires) and correct at 60PSI (bike tires).