Had an interesting conversation with my co-worker today. He is the one I mentioned above who crews for Rare Bear, which by the way didn't fly at Reno this year due to lack of funds.

He said they removed the fold up wing tips, about 3 ft each side, and made new tips. They saw a big speed increase but couldn't remember what it was exactly. He said those tips where originally designed to break away in 8g plus dive, also removing some aileron.

He said the plane didn't turn tight enough for the decreased span to cause a higher AoA in a turn, and in his words "it has so much horsepower and torque it wouldn't have mattered".

He also mentioned a term I hadn't heard before, he said the overall "wetted area" (air going around the wing?) was decreased by removing the tips, and this also drecreased drag as does less frontal area.

Based on what he told me and all the above posts, I would conclude that if you wanted to turn as tight as possible without loosing much speed, a high aspect ratio wing would be best. You can see this in the design of the current Q40 pylon planes. If tight turning radius is not important a minimum span would be best for overall top speed. He also mentioned that the Rare Bear makes very "interesting" take offs and landings due to the higher wing loading.

One other note, when I was flying Q500 several years ago, if you banked the plane over and pulled full up elevator you could hear the wing start to stall and see the plane lose speed. If you pulled just enough elevator to keep it from making that sound it was noticably faster in a turn.