Depends on the pilot skill set and what is being flown... A heavily ballasted sloper can handle 35... and an indoor only foamy, A/C type breezes! with that said.. a rank beginner will want 10 on the slope and 0 mph coming from the A/C ducts.

THe stronger the wind.... the less holes and more constant. This usually occurs near 20 + mph... And yes, the airplane doesn't know it's windy.. but they sure do like it more when it's not!