I've now got 16,000 miles on my DX AWD Auto. Here in Jersey the summers are hot and humid. The AC gets a workout. The weather has started to change. (4 seasons). Those 16,000 miles have been done mostly on the hwy's of the metro NY/NJ area. I classify myself as an "assertive driver". I avg. 80 mph and jockey for position among the other metro NY/NJ "assertive" drivers. Merging onto the NJ Tpk means going from your 40 mph merge ramp speed to 75-80 mph as fast as you can. This is where my E's breathing modifications really shine. I digress. The AC knocks off at least 2mpg and does effect performance somewhat. Tonight the temperature is in the 50's. My road trip was to Long Island. Windows were closed and only the fresh air vents were on. NJ Tpk to, Outter Bridge crossing, to Verrazano bridge to Belt Pkwy to Southern State Pkwy. NY/NJ is home to millions of "assertive drivers". I drove with my windows closed, AC off, vents on in my typical assertive style avg. 80 mph and I still got 23.75 Hwy. mpg based upon a 185 mile round trip. Not bad. I'm going to add the cai next. That little 2.4 I Vtec loves to rev. 3-5000 RPM's is a nice sweet spot for this E.