As always Dan,nice trees.
I recently asked the designer od the many shapewayOn30 PBR stuff to do theD21 in striong white and flexible, as it halved the price, he did so , so can be a great one if you have a question or wish a variation.
Haven't bought it yet, but will. Now to work out a mech for it. I were thinking the HO Roco 08, or OO version.