There are advantages to the fsw, in that the spanwise flow that normally contributes to bad tendencies of swept wings to tip stall. The reverse is true here. The planform is very resistant to tip stall. It generally can fly much slower without high lift devices as a result.

The problem for planes at high speeds and g's is the structural problem of the wings trying to peel back on themselves. This is a consideration, but not really a problem for models. Thick wings as found on most sprot planes can easily be built stiff enough to take the stresses of sub-100 mph flight. There have been a few kits & plans out there.

There have even been scale jet models of the X-29, but I haven't seen one fly.