So, just a question to anyone else who has played co-op.
Do you still loot ammo properly?
Because when I play co-op neither myself nor my friends loot properly.
Instead, we're able to pick up all ammo regardless of whether we are full or not. The only things we can't pickup are grenades, rockets and health/O2.
Furthermore, the host of the game can't even tell when he is full on ammo by looking at ammo lying around. It will never come up with a full symbol, but for the guest, he can. But even if it says full, he can still pick it up.
This was in Borderlands 2 also, and it's really annoying. If it's just us who has the glitch then I'd be surprised that it persists just for us in BL1.5.
If other people have it too, then I'm even more surprised that it wasn't fixed.