Input Buffer - 0.5 (max 1)
Priority IB - 2 (max 2)
Priority Input Buffer states that weapon swapping is considered a PRIORITY function. So, it only makes sense to make sure that is maxed out.
Input Buffer essentially remembers your attacks so you can press M1, M2, M1, M1 and the game will remember it.
Not very good if you need to hold block or do a push attack in the middle of that chain.
So, I keep my Input Buffer in the middle so I don’t get stuck having to finish out extra attack animations and have better control over my attacks.
Higher Input Buffer - easier opportunities for dishing out combo attacks in a chain and game will remember a longer series of your button presses
Lower Input Buffer - more control over your attack chain as it remembers less actions and therefore your emergency blocks will register much faster
It basically comes down to personal preference.