I have always preferred the Pressurized check. Seems the atmospheric side was a huge waste of time just to tell you it is low and to drop a few ML at a time. I would always check the atmospheric side, if no fluid on the dipstick, drop the dipstick in the toilet bowl to see how much to service. From experience, I always dropped 1/2 qt less than what registered on the dipstick. My .02
Gary