Hello,

Yes, it's Rhino with the VSR Shape Modeling 2.0 plugin. The plugin is twice the cost of Rhino, but it's paid for itself a few times over with its version 1.1 capability alone. The Multiblend feature is new in 2.0, I thought I'd give it a try. I'm sure that surface can be tweaked to be even better with VSR by someone who actually understands surfacing concepts. Here is the 3dm.