Auto flip play on defense off or on?

Ive always had it set to on so that the CPU will automatically flip my defensive play to best match the offense. The only downside is if I prefer a certain player like a OLB or LB to blitz or drop into coverage but because the CPU flips the play it might be the other OLB or LB that blitzes or drops into coverage. Its no big deal when that happens but for instance id rather have Willis blitz and user him with his avalanche instead of having my other LB blitzing and having to put him into coverage and user Willis. I could always manually flip my defense but it seems like you wouldn't have much time to have your Players shuffling and moving around and could be caught off guard easily. Also I really don't know when to flip the play so I just let the CPU do it. Are there any benefits manually flipping your defensive plays or letting the CPU flip them? Cause you dont know when the offense has their play flipped until your at the LOS and by then you don't have much time until they hike the ball. I do prefer knowing which players are blitzing and dropping into coverage though due to certain abilities and some players who play MCV or ZCV or rush the QB better than others though. Any tips or advice on play flipping for defense? Ibe always just let the CPU do all of that.