I'll second the entirety of Eddy's post, and refute the StreetFighter.
I run Blue Thunder in all of my engines. Why? For the most part because of what Eddy has said with respect to availability...and the fact that my engines seem to run cooler with it. I tried a couple other brands before settling on Blue Thunder, and the smurf juice (because it is blue) seems to work the best for me.