If you really want sharp, laminate in a little carbon fiber. I've seen models with TE's you could cut with if you wanted to.

But the hanger rash just sucks. Personally, I'm forever bumping in to things moving my planes around the house and such.

Also, the extra drag on an acrobatic plane isn't bad as it helps with braking on the vertical down lines.

Oh, if you do have a flat TE, be sure to make the corners nice and sharp, don't round the TE. The rounding promotes flutter, a more squared off edge seems to flutter less.