It took my squad of 4 people 6 missions last night to get 200 kills with the 500 kg! That was on difficulty 7 with everyone running it as the free stratagem. It was soooo painful!
Nah, no one brought extras. 4 bombs a person seemed like overkill. Though most of the time we were using them on Bile Titans, which must have lowered our overall kill count. Still there were a few times I'd throw one on a group of bugs expecting a dozen kills and would get like 3.