from what i can see on greatmodels.com,
the F/8 (dr9013) comes w/ snow tracks.
the Aus F (dr9028) is shown as 40L/48 w/ Ostketten so i don't know if it is armed different than the other, but i believe Ostketten to mean "east tracks' so they might be snow tracks too.
the Ausf F is shown OOP, but w/ a greatmodels price (when it was available) of $22.40
the F/8 is shown as $38 retail, $30.40 greatmodels price.
not sure if you were looking for more data abt the kits, or the actual vehicle differences.
but that's all i know!
here is a link to a review, but it is a III Ausf B
http://www.missing-lynx.com/reviews/german/dml9008.htm
good luck.