606 doesn't really seem very interesting. Geo on everything except the 707 that FB / Carbonda do is very similar, and nothing with a more relaxed front end and steeper seat angle in the larger sizes. May not be what interests you or others (it does me), but my point is that they have several models with relatively little differentiation.
I'd love to see something like the Argonaut GR3 - but with the rear triangle adjusted for 2x.