You guys need to remember that not all tire gauges read exactly the same, even the outside Barometric pressure can influence what your low pressure tire gauge will read with the same amount of air in the rear tires
My message is use your tire gauge on your tires only and DON'T loan it out to anyone
I will use one of my cheaper gauges on a another racers tires but I won't let him use my gauges at all, that is after having multiple good low pressure tire gauges ruin by loaning them out to someone I don't know or trust