Thanks for the input. At the moment I think I've got an ok workflow going from SU to 3ds Max and using Vray there. I'm at the early stages so we'll see what snags I run into. My biggest concern is materials. If something changes and I have to swap out models, I'll have to reassociate every material on every object again. I'd thought about breaking up my whole SU model and making it all one big group before importing to Max so I'd just have to reassociate the materials on one big object but then I'll lose any benefit from instances and layers.
-Brodie