On my f 18 and scorpion i have elevons
on the f18 the are used for landing and slow flight because the ailerons are not that
effective
in your application i would use them for landing if you want to use the ailerons for
flaps, but turn the aileron function off when you turn the elevons on.
reason being with the ailerons as flaps you want them down all the time,
if not when you make a correction you lose massive amounts of lift on one wing and it gets pretty hairy.
give it a try you might like it . it may not work worth a flip.