I have found AAC to be good once it is at running temp. When I got a Sirio for the first time I had no end of trouble because I was turning the needles too soon. Now I know what I am doing I have been won over. The power is great & they seem to hold a tune very well & no problems at idle. This is even with the evo 1 composite carb. Now all I need is RB to offer an AAC version
