why not both. the idea is to have limited weapon choices. i thought about doing one or the other. cowboy doesn't gave machine guns and grunt doesn't have a decent sniper weapon. but neither has missle launchers, sigh.

I am thinking about doing a Cowboy/Grunt/Explosive build. The character will not be using light armor or any critical chance/Crit damage. Also no sneak. I think I might have enough perks to pull it off by not going that route.

Why not, especially if you want a more melee focus. Grunt gives a 25% damage bonus to Combat Knives, Cowboy to knives in general. Add to those Piercing Strike, and you have a pretty deadly melee character.

Both perks stack with "Chance's Knife" making it deadly indeed, since you do double damage in vats and can strike with it quite a lot due to low ap cost:) I have taken both perks on a few gun fighter/gunslinger characters, but as I get older im a lot stingyer(stingier?) with my perks, so i will choose one or the other, or neither:D most times I play on 30 level cap so I don't have too many to just spend:D