Kix, I agree with you..to a point. Yes, for the average torch user that cuts and heats up here and there, some sweating might be indicative of a leak. But sweating is not a function of flow rate as much as it's a function of volume. When the volume of gas is very high, like if 2 or 3 lines are run from one regulator, freeze up is common when the ambient air temps are cold. When we service our bulk tanks, we run our entire plant from a 12 pack bank of 98/2 mix. We average 8-10 cfm of gas volume, which is 540 cfh of flow into the main head line. No matter if the air is 95, or 25 degrees, it takes about 15 minutes for the regulator to start icing on the outer shell and out feed hoses. Even in the middle of summer, we always put a halogen light near the regulator to keep it from freezing up.