ok my brother owns one of our car audio shops here in Myrtle beach. he sells kicker diamond mtx re and fi audio and a little of the mmats stuff. the best subs ive heard for spl are. the RFL, the BTL the solox and the juggernaut 18 and 15" and the xxx. one of the best subs i have heard in the shop is between the Daimond D9 and the BTL. if you go with a solo x i wouldnt run it for daily you may burn the voice coil out. if you really want spl go with the rfl but if you want good sound quality go with the D9 or the BTL you will get awsome spl and sql and you can run it dialy.//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif