Fine, but so long as your CG is in front of the aerodynamic centre, and it will be for a pitch stable model, then you don't need a reflexed airfoil, any good symmetric (zero camber) foil will do. This stuff has been known from the early pylon racing days, when 0.19 powered deltas ruled, way back in the early `60's. The foil you have chosen will result in an inferior flying model. Remember, it's a delta, not a `plank' type flying wing.
Evan, WB#12.