I am about to replace my OE tires and wanted to know if the information I read on the web is correct about TPMS replacement intervals. I have read that the lithium ion batteries have a life span of about 7-10 years or ~100K miles before needing replacement. My Z has a manufacture date December of 2012. So I am about to be in that window. I have looked up the sensors online and 4 are ~$200.00 plus you have to have them paired to the DIC so the display is correct and that will also incur I am sure another charge of at least 1/2 hour of labor so the price of the tires plus all the other stuff starts to add up. Mounting and balancing tire disposal etc. Is it best to just bite the bullet and replace them now or is the life span of the sensors actually much longer than the 7-10 years I have read?