I have the TST system and it works very well. As was mentioned there is pretty long lag time between when the monitor loses contact with a sensor, and when it notifies you that it has lost contact, an hour is about right.
I have the flow through sensors on steel valve stems and if I had it to do over, I would opt for the regular sensors. The flow through are a real PIA, as they restrict the air flow so much it takes a long time to add more than a couple of PSI. I unscrew them rather than use the flow through design. Steel stems are a must IMO.