Glaser is going to be tough to beat, especially on the spin front as they have the F18/F16 development experience. What Lee is describing is exactly how a modern F18/F16 and even a less modern (04') Tornado kite perform. They twist off automatically during a gust. I wouldn't want a smaller kite and at least the 2013 Glasers I have are cut deep enough to go downwind in the light.

It may also be worth a talk with Hyde sails (Simon Northrop), they too have the F18 experience but I'm not sure they have the Glaser experience. Performance is also making sails for the boat and they have fast F18 kites. Some MD guys may be getting some older used performance kites for the N20 for comparison.