Some will; Check response graphs for them. I've got some fours in one of the cars, and they get down a little bit; Not enough to excuse the lack of a dedicated midbass.
Between them you will notice a big difference...Theoretically you can just play your sub higher to xover better, but you will lack essentially the Kick of the midbass up front (80-220hz) that only a larger driver can provide. Also if your sub is suspect in SQ and cant play those higher frequencies well you will feel a void..