RE: 2 blade vs 3 blade
It all depends. If both arrows pass through at the same spot than the 3 blade with a larger cutting diameter will leave a better blood trail due to the larger exit hole. However, two blade broad heads have a better penetration so in theory if a two blade passes through where a three blade might not have then the two blade would leave a better trail due to the exit hole. All in all I doubt there is a noticable difference although I prefer the three blade.