My 507 system is almost 9 years old. I am hoping the original monitor will die so I can justify one of the new color ones. Oh well, such is life. I only replace my batteries when they die and they last a couple of years even when not removing them when not traveling. OK, I'm lazy. I have had 2 sensors fail over 9 years of full time use.
Ed
KM4STL
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch, Progressive Industries EMS-PT50C, TST Systems 507 TPMS
2010 Jayco Designer 35RLTS,Cummins/Onan RV QG 5500 EVAP
Fulltime since 2010