What is the difference between these two TPMS systems.

I had flow through sensors and never had any trouble with them. Airing up the tires was no more difficult than if they were not there. The advantage is that I could LOCK them in to position which discouraged theft of the $50 sensors.
The sensors that you have to remove to add air are either kept loose or you have to use an Allen wrench to loosen them each time you want to add air.