After much investigation, I purchased a TST system from www.technorv.com. I learned that TST uses GE circuitry. It is the things you can’t see that makes the TST great. TST has roots in the trucking industry, and their quality keeps up with million mile trucks, so that is good enough for my RV. I love how the monitor screen scrolls through the tire data as you are going down the road so at a quick glance you can see what is going on, not all systems do this. TST also has available flow thru sensors. Then there are systems with user replaceable sensor batteries or a system that has 5 year sensor batteries, that are not user replaceable (You send back to TST after 5 years and they replace them for you for a fee). TechnoRV has installation videos for both types of systems, and was very helpful during the buying process.
