Depending on the type of machine I get on the render farm I'm getting about 15 hours per frame on 6 core boxes and 3 hours on 16 core boxes. The biggest challenge was getting it to render without any artifacts such as popping geo and shadows, along with holes in the mesh. There's still some geo hole issues that I've determined are probably my fault as I am likely flying the camera too close to geo or through it but I can accept that for now.
I spent a of time testing different settings at low res until I got something that worked. It seems I'm about there now but at considerable render time hits, though taking into consideration the HD resolution and the millions of micropolys represented here that really isn't all that bad.
