Just like traditional rubber valve stems, TPMS valves breakdown. It's recommended that you replace the rubber grommet, retaining nut, valve core, and valve cap every time the sensor is broken down from the wheels. Mention the price difference you found and I'm sure your local store will match it.Have a question, when getting new tires for the Mazda 3, I know you recommend the TPMS rebuild kits, is there a problem having new tires installed without them? Will Discount Tire have a problem if I refuse the rebuild kits?
Reason I ask is you charge $7.50 each and I can get them from rockauto for $1.19 each. And being on a budget every little amount helps.