I'm running good old R-12. I keep an A/C thermometer in my center vents and typically at quitting time the interior of the car is 110-125 dF, ambient temp is 90+ dF. In less than 3 miles, in town traffic, I'm showing 40 dF at the center vent.
While the temp is 40 dF at the center vent, due to the high interior temp I don't "feel" cooling until I hit the open road. Once I get up to speed, the interior cools off quickly. Seems most of the heat is radiating from the dark brown MB Tex. By the time I get to the house the steering wheel is almost too cold to hold on to.
I'll stick with R-12.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.