Fours, good.. Eight, better.. If you have the money, go with the 8's.. If the room is smallish, 4's may be perfect ?
Music, or movies ? Loud, medium or soft volumes ?
.223 or .308 ? Both get the job done, both have their pros and cons.. Ones just a liiiiittle louder than the other..
Buy both, try them out, and send one set back..


LFE ! The rest is just details..