Top Fuel is pretty well made. All three of my engines have used top fuel as well as other brands (Trinity, BT, Wildcat).... and on _each_ of those engines, the minimum difference in temperature when using Top Fuel was 10F, sometimes more using the same tuning settings. Impresses me. If I need more nitro than 20% for racing and such, then I certainly use something different, but Top Fuel is just plain Good Stuff for all around use.