TPMS Question

I just installed a TST system. Love the guys at TST by the way. I called them before ordering and they patiently answered all my questions (many the same as yours) with enthusiasm. I got the 507 system with replaceable batteries. The TST albeit a bit cumbersome to set up, worked flawlessly on our recent 2000 mi trip. As far as extenders- yes they work with extenders. I did have a clearance issue on my F53 front wheel simulators. The simlator (glorified hub cap) did not have enough clearance for the additional room required for the sensor. I used metal snips and trimmed it back (took my time and it looks factory - if you could tell at all). I doubt this is specific to the TST as every system will need additional clearance. I have never heard anyone having to do this so either it's so normal that no one mentions or I have something unique. Hard to believe on the latter. As for immersing them, I can't say. THey work well in rain, but fully submerging them I am not sure. You may want to call the brand you are thinking of. After having a TPMS and allowing me to set my PSI correctly (for a better ride) I would never be without one.