Don't use the 30%, ounce you use it you won't want to go back to 15%! Saito's love 30%.
But all kidding aside the 72 on the mojo will work great.i had one on a mojo for a whole summer,good power but it wanted to torque roll in a hover real bad.i had a ST 51 with a tower hobbies muffler and the mojo had every bit of power the 72 had but a lot less roll in a hover.
real nice plane you won't regret it.
ENJOY!