Turrican or Mega Turrican?

Which should I get??? I am alittle new to Turrican, never played the Amiga ones (never even SEEN an Amiga lol). I have and beat Super Turrican, didn't really get into the sequel. I played Turrican and Mega Turrican on the Genesis, and while Turrican is more oldschool (it may very well be a Turrican 1 or 2 port, not sure which one), it is hard as hell. Or there is Mega Turrican, which I hear is Turrican 3, only on the Genesis. It plays alot more like Super Turrican where it has the better music but is pretty linear and not as immersive. I do want both, but which should I get first? I HAVE played both on ROM, but I just can't decide. Any help? Thx.

So I just bought both of the Turricans for the Genesis today, I look forward to playing them! Sadly, that will probably be my last Turrican purchase (until a newer Turrican comes out). I still don't have intentions to buy Super Turrican 2, not now anyways...