thanks for all replies so far. two questions:

1) does the tire monitoring system SHOW you the actual tire pressure, such at 33psi?? or does it just indicate a change. i would like to see the ACTUAL pressures... so that's easier to monitor and be sure all are set the way i want.

2) obviously it seems a winter tire/wheel won't use the tire system, right? i've been using the Michelin Pilot Alpins in the winter which are great with 17" wheels. i don't know if they have run flats for these. if not... then what happens if you get a flat... because there is no spare in this car, right???