Gotta say, they're bigger than I expected.
From the update:
Well, it's the end of day 2 and things are moving right along. Today the 3D prints for the 28mm scale Terran Light Mech arrived and I took some photos. This thing is actually pretty huge. It's exactly 2x bigger than the 15mm scale, so I guess it's more like a 30mm scale mech, but who's going to nitpick over 2mm when the model looks cool? :) Here's the pics!