These figures print quite easily with PLA. I printed the alpha and beta with different colors of PLA to differentiate them. The surface model of heme does not fit very easily into the binding pocket, but the ball and stick version fits quite well (http://3dprint.nih.gov/discover/3dpx-001633).  I used rare earth magnets to attach the 4 subunits. This part was tricky, but it was made easier by referencing the figure on chimera.