Shaving Brush, boar or badger?

Generally speaking, badger. Badger hair is softer and holds water better while boar bristle is significantly stiffer against the skin. Badger brushes comes in different grades offering different degrees of softness. That said, some shavers enjoy the invigoration delivered by a stiffer boar bristle. Colonel Conk carries both badger and boar, and you might even consider a boar/badger blend.