The aggressive dogs I've encountered are either barkers or biters. The former make a lot of noise but pose no imminent threat. The latter group is the problem. Any biter over 30-40lbs can be a serious problem, one that requires lethal force more often than not. My first choice is a pistol ... then spray. The baton isn't practical IMO as using it means the man vs. dog confrontation is now hand to paw, and way too close for comfort. A well placed shot or two will prevent the altercation from getting into CQC. If I was encountering threatening canines on a regular basis, I'd consider the Governor with mixed .45 & .410 loads.