So everyone says the thermo on most are inacurate. Whats the best method of figuring the temp? Did a pork butt a few weeks ago, and although it turned out awesome it took a bit longer than expected. Getting ready to do some spare ribs tomorrow and thought I'd run a pan of water to see what temp it reaches. The door unit thermo at 250, water temp is 160 (checking with a digital thermo).....doesnt want to get any hotter it seems. What about a potato? Think that might help? Should I just buy a therm I can put on the rack along with whatever I'm cooking? Just trying to get a handle on actual temp vs. what the manufacturers thermo says.