Any program that can load DXF files (a simple CAD like drawing) exported from Hammer can be loaded into a modeling program and fixed up to be a model. Aside from that, using the power of a modeling program would be far better than using Hammer.
I side with Max, but Blender certainly impresses me with its open-sauce mentality. I've used it and its cake.
I don't think you should let anyone tell you what to use. First find out which programs have good plugins and compatibility, then try some and get a feel for some and choose the one you like, or if you believe in destiny, let the program choose you.