My fingerprint sensor is very accurate. My problem is that in reaching to get the phone from my holster (yes, I'm that nerdy), I typically accidentally touch it enough times that by the time I'm ready to unlock, I've accidentally "put in an incorrect fingerprint too many times and must now wait 45 seconds before trying again." or some similar message. Anyway, I'm getting used to taking it out differently, and once its unlocked, the Galaxy Watch keeps it unlocked through Smart Lock/Trusted Devices. But overall, so happy to have a regular fingerprint reader back instead of Face ID or the in-screen ones of which only the One Plus 7 Pro's was really good of the phones I tried.