I run my a/c/climate all of the time as well. It rob's my V8 AMG of precious horsepower at those crucial overtaking moments....but I can live with that .
....increased fuel consumption , not something to consider when driving an old N/A V8
I took my 124 to get regassed after changing the condenser. When I went to pick it up they told me they had tried filling it but the compressor never kicked in so they emptied the system again. I had to point out that when the light was on the A/C was off, seemed counter-intuitive then and it still does now. Nice to know it has changed for the better (more sensible!)
CLS500 4.7TT 2012,, SL350 09, 996 cab, all current. Gone :CLS 55 E500 W211, 2x M5s and too many 911s
My wifes SL is red light on a/c off as was my w211 but my cls55 is red light on a/c on. usually the revs drop if the aircon is switched off and vice versa, which is another guide if you are not sure of which way your light operates.