The v1 Origen was the version with two completely separate
juice wells. V2 and V3 decks are identical and both have a shared
juice well. The only difference between the two is like inswyva said, the fins on the top cap and a little large air holes. The BF pins work with either version.
I'll also mention that if you get a BF pin, go for the stainless steel version. I broke one of the brass versions tightening the center pin down on my v2 and with the ohms from the type of coils you will be running in the Origens, you will not notice a difference in conductivity between the pins, but there is definitely a difference in the durability of the metals.