We heard it all before we moved too. We quickly figured out the people who were the most negative had never lived more than 50 miles from where they grew up. They simply could not fathom living "away from home".
Even on the hottest days here, it is still very pleasant outside in the mornings and evenings. I am also amazed at how quickly we adapted to the climate here. By the end of our first summer, it was only when the temps hit the upper 90s that it seemed uncomfortable to be outside for long periods of time. Up north, we considered it "shorts weather" when temps hit the low 70s. Now we wear long pants and grab a sweater before venturing out when it is that "cold".
