So far so good. Used them every day and used them for the last 1500 miles. It seems fairly accurate, maybe off and on, but no more than 2lbs. (who knows, maybe my sensor is off). I like the fact that they seem to be getting air in the tires better since I don't put as much air in as I used to. I can also attest that it is waterproof as I got caught in some heavy downpours during the trip.