Originally Posted by PremEx
As a result, you often see 1Ks sitting in the back when Premiers are being moved up front, simply because 1K's don't have an unlimited supply of Domestic upgrade media.
That never occured to me, but it makes sense. For me, at least 40 500-milers a year (plus any CR1s) is a ton, but to a 1K that would hardly cover everything.