I recently used my brother's M4 Fairway Woods and noticed soft feeled club face and the balls I hit didn't go straight (I still use M2 or R11S in the local tournaments or skins game). Are your M4 (or M3) Fairway Woods like that? I thought about updating my Fairway Woods, but I'd like to ask if how you are hitting your M4 (or M3)s.
M4 is a bit easier to hit. It has a little spin which makes it easier to launch/control. M3 has a smaller profile and less spin which makes it a bit easier to shape and can be a monster off the tee depending on how you adjust it. M3 is typically best suited for better players. We're super excited about M5 and M6 this year though!