Softlite Imperial vs elements

Does anyone know the difference between the Softlite Elements and Imperial?

I think Dave already posted this, however, the differences are predominantly aesthetic.

I realize there is the slight difference in U-Factor and air infiltration, however, the "unofficial" reason that I was given for that delta was an effort to create some differentiation in the product lines.

Comes down primarily to aesthetics when you are comparing those two. Can't go wrong with either.