Well ya the tiny marks on the back I figured were pretty normal, they're also there on my kbc clear keys, & on some china keys.
But low and behold there aren't ANY tiny back marks on any of my abs sp keys, so you're right there. & the old zerg sc2 2shot sp keys I have also have perfect front sprue marks. So I guess it's just luck, or the sc2 keys prove they've gotten lazy in that dept.
If you look in my first pic, the 3rd key has a TINY front sprue mark. Loving these, VERY nice overall.