Well here's my update. The car stopped belching grey smoke (it does that once in a while on cold mornings) with the 100 octane gas. My mileage stayed the same. No noticable increase in power. The most significant thing I noticed was the temperature of the engine. Usually the needle hovers just to the right of the midpoint of "8" of the 180 degree marker. With this gas, the needle was just a hair shy to the LEFT of the "8". Pretty interesting eh? So... my observation and subsequent conclusion will be I don't think I'll be buying it anytime again soon if all its going to do is run a few degrees cooler.
