Just tried my new Slime psi digital gauge. I had the previous version and the difference between them is the newer version claims it does not have that initial hiss when you put it on. It sure doesn't. I put it on no hiss and the readout showed 39.5 psi(cold) and thought that was too easy so I did it again....and again.All tires except one showed the same psi.All now have 38.5 psi.Car came with Bridgestone tires and the only psi recommendation shows no more than 51.Door frame says 35 psi.
But for those looking for a hassle free gauge this one works great.