I actually bought the Smithsonian version. I talked with Digital Blue's tech
support first and they said that except for the branding, the only
differences were the color of the plastic shell and a minor non-functional
part change.

I actually got my Smithsonian version in CLEAR plastic. The microscope lens
tubes are still opaque, but the rest is clear, which is semi-cool since you
can see the chips and wires.

The non-Smithsonian version was on back order everywhere I looked when I went
to buy a QX5 about 8 weeks ago, so that was my only choice.