I bought a tst 507 after having an unseen flat and driving for a mile with a shredded tire beating the side of my windjammer. If people hadn't been honking and waving I might have driven further. Had to replace the bottom metal on that side.
I moved it to my Montana fifth wheel, got a high temp alert near Tampa, luckily there was a rest area right there. Got out and looked and my passenger side rear tire had all the inside tread scrubbed off, turned out I had a bent axle. If I hadn't had the tst I'm sure I would have kept driving until it blew.
Bought 4 more sensors when I got the motorhome, then I bought 4 more after that for the silverado we tow behind the motorhome, total of 12. Kind of expensive but well worth the peace of mind.
Had a high heat alarm go off on the silverado toad, at Tampa again going to Florida this year(Tampa hates me I guess), pulled over at the very same rest area. Had a hanging front brake on the passenger side of the truck. If I hadn't had the tpms I'd have kept driving until I possibly blew a tire or had a fire.