I did the retract thing back in the 70's. I got back into pattern in the 90's using fixed and I haven't looked back since.

I think the Bolly swept gear is a very good choice. The gear is designed to flex and give. They will take a surpisingly high impact load before breaking or tearing up the airplane. I have a set that were in a crash that totaled the airplane and the gear split length wise. I repaired them with thin c/a to the split and put one layer of light c.fiber on the bottom with thin c/a and they are still serviceable on my new airplane.

May not be the lightest gear on the market but are the more durable and shock forgiving.

Wayne Galligan

As for aerodynamics.... the biggest factor I have seen is the wheel pants. If the pants are not lined up it can have an influence on trim and some drag issues. I am sure it may influence knife edge some. Retracts have issues with a big hole in the bottom of the wing so there is probably a wash on the influence of trim on eiither set up.