Just want some suggestions on what to get. My first option would be to get 2 MRX 518s on the outside and 1 528s in the middle or just get 1 srx 728 dual 18" and put that in the middle. Out of all of that which option would you guys go with. Of course everything is powered by crown amps. Would that srx 728 be louder than that mrx set-up. Any suggestions help, thanks.