It's very stable, which is actually much more important than absolute accuracy since you want both tires to be the same pressure on each side, plus/minus half or even an integer PSI value (the is 3%). at 30 psi) is not critical. I have to press it against the valve very quickly to keep air from escaping. I wish it had an extended cartridge tip as I'm not very fast at my age :-) but any that had an extended tip didn't have the Bourdon mechanism. The seller got back to me very quickly when I had a small problem and sent me instructions on how to fix it. Overall very happy with this purchase and would recommend to friends and family.