JR 8103 or the Futaba equivelent is the way to go, unless this plane
you're speaking of will be your one and only gasser. Tho it's not
recommended on quarter scale and above, you might get away with
y cording the ailerons on the 28 %. Rather chancy, tho. Thinking ahead,
if you decide to go to a larger airplane, you'll likely need additional mixing
functions. You might try E-Bay or classified Ads for used and have it checked
out at the authorized location. Might save a few bucks that way,

Gerald