Tomorrow we start our first road trip in our Lt. Platinum 2008 SRX. V8MRC,Luxury pkg,Ultraview,Sport pkg,18" wheels. Had oil changed at 1200 miles (2235 now)
When I put air in tires-30 front,32 rear with a very accurate guage which reads to 1/2 lb, the DIC reads 32and 34. Which should I believe? Are the Tire Pressure monitors more accurate, or is 2 lbs nothing to worry about?

If you're sure your guage is correct-----stick with it's readings. The TPMs are not highly accurate.

Both my SRX and my Corvette are dead nuts on the money with my $100 tire gauge. But if you're only off 1 or 2 lbs. it's not much to worry about.

The TPMS is far more accurate than almost any tire pressure gage you can buy on the street. The reason for discrepancies is update rates and the fact that 1/2 mile of driving will cause a significant amoumt of temp/pressure increase. When the vehicle is stopped for more than a short while the TPMS update rate drops to once per hour. The car has to be moving at least 20 MPH for the update rate to increase and by that time the pressures have already started to build. Check the tire pressures in the morning before you move the car but don't adjust them. Check the TPMS also before you start to move for best correlation.