Hi,
Its looking great. I'm averaging about 40fps (40-50 before you added the specs)
Have you looked into using Papervision 3d? It could give you the ability to do more texture related stuff and might be comparable in speed.
Its what we used to do 3d conversions for a project for coke that will launch soon.
Its looking awesome. As far as 3d exporters, not sure how much interest or use you'll get. I'd query about the usage of Webhammer, to get a better idea of how much such a tool will get used.
C