Title. Posting this while Xbox Live is down. Funny thing is, I beat the entire storyline (um, "story" mode and then some before I ever used any ammo synth. I was doing Sepiks Prime bounty, noticed that my primary ammo was almost, but not completely, drained. I've never been one for surprises, so I popped my very first ammo synth. Bittersweet accomplishment. Still have yet to use a heavy ammo synth, though, so I got that going for me.