I can definitely confirm that, at the very least, the heavy ammo perk doesn't stack when combining Armamentarium and Willbreaker's Greaves. I tried all three of the options: (each piece alone and both together) using a 4-rocket launcher, a 6-rocket launcher, and a heavy machine gun. Load it up until you can't grab heavy ammo anymore, fire down a little, switch loadout, repeat. Same number of bullets or rockets every time. I haven't tried doing the same thing with secondary ammo, melee speed, etc, but I'm positive I don't get more heavy with those armor paired. Its made me rethink my armor - Armamentarium makes a lot less sense knowing I don't get extra heavy from it. I miss the second grenade, but using Alpha Lupi instead means I've got increased heavy, special, *and* auto ammo, leaving my gloves and helmet to perk auto reload and whatever goodness I can find in a helmet. Good luck out there Gaurdians!

That a funny because I could have nine with hezen vengeance/raid boots and lucky raspberry. Thanks for your retarded input though m8

It was oct. Update because I use to get 9 rockets with raid boots and armormentarium now I get 8. Grenade speed does stack confirmed this two days ago when my buddy jamarcus russled a grenade across the map. Will post link if I can find it.