Mike Buckley,

I have single servo, torque-rod driven flaps inboard (between the nacelles) and separate servo driven ailerons outboard (1 servo per aileron).

Mine is also around 10 lbs and lands at a reasonable speed without using the flaps. A little down elevator gets mixed in to compensate for a nose up pitch when flaps are deployed.

I also have a small amount of flaperon mix in the outboard ailerons. As such my Duellist can land very slowly.

You don't need them, but they're fun to experiment with.

I find that I only use flaps about 50% of the time.

-E