I have the Pressure Pro System. For the most part it works well. It doesn't give you accurate pressure readings, but it does notify you of a change in pressure. Every once in a while you will get false alarms due to a bad transmitter, but every time I have had a transmitter go bad, they have replaced it for free. (you have to send the old one back.) Overall, I like it. I'm not sure how I'd feel about a system that went inside the tire. I like that if the transmitter goes bad I can just unscrew and send it back in. It also occurs to me that the transmitters, at $50 a piece, are easy targets for thieves. Never had one stolen, but it wouldn't be a hard target. Of course, the second it is taken off your tire, you would hear an alarm... but then you have to get your clothes on, get out of the bus, kick somebody's butt... bla, bla, bla.