RE: wing loading vs. preformance ???
The 4m at 12 oz/sqft will likely be a real floater that can kick out when needed thanks to the airfoil. Scale effect and reynolds numbers you know.
The 5m at 21 oz will likely soar just fine but even at that size and with that airfoil I don't think it'll fit in the floater class.
Those are sure some hella big options for models....