I am running a 170 deg T-stat with the stock tune at the moment. With my custom CAI, my IAT temps are at or below Ambient on hwy, and my engine temp ranges from 179-185, usually in the low 180's. Engine temp was at least 5 deg higher when I was running the AirAid Cai, and IAT temp was always several deg over ambient. My fans have not been set to turn on earlier. Yes that is a very good idea, and would help even more in town, though Flex runs cooler than my G8, which has a tune to take advantage of fans, and 160 deg T-stat.
Where this helps at the strip, is that vehicle doesn't heat sink quite as quickly, and recovers sooner. It's a good idea even if you don't have your tuner change fan on temp.