I'm glad they responded, pywackit. You can expect something like 300 more RPMs with 30% nitro over what you would get with 15%. I always get 15% because it is available and the Saitos run fine with it. I add castor to Omega 15%. I got a quart of castor from the hobbyshop, but you can also use castor from drug stores. It costs a bit more but it works just as well.