Forward sweep works well at subsonic speeds for a variety of reasons:
Tip stall is gone so you can drive the wing really hard in corners
For a flying wing, the cg is forward of the wing root so that there is room for tank and engine (or battery!)
The wing lifts like a high aspect ratio one, but has pitch dampening like a very low aspect ratio. Thus, no bobble in hard corners.
With the forward sweep, the elevator has a good tail length to generate turning force with little drag penalty or disturbance to the root wing lift.
It looks WICKED in the air!
I am nearly ready to publish this baby, the Sky Streak.
Flying Models wants it. Part sets will be available from rsmdistribution.
250 sq.in. Weighs 6.7 ounces finished. Flies like a dream (no not a nightmare!)
Further comments on this model will be found in the 1/2A section, I shall not divert this interesting thread further. I MAY still have a photo of a factory display model of the FSW P-51. I'll look for it and post it if available.