I've printed this in both orientations. Here's the basic rundown.
Vertical (narrow flat edge base):
I needed a brim to keep the thing from toppling after around 60% completion. The faces of the print are really nice at .1 thickness. Using "Lines" for the support type in Cura seemed to be the easiest removal after printing. Printing takes considerably longer, but the result looks better than a horizontal print.
Horizontal (default "flat" orientation of the model):
Much better structural strength (based upon physical stress potential expected through everyday usage) than the vertical print. Though the fact that you're removing supports from one face means that it isn't as smooth as the other side. But then - it's gonna be behind an ID card anyway, eh?