I've had these subs for almost three years now. Very loud and durable subs. Had four but took two out to give to my wife (I stopped competing). Could be a little cleaner sounding, but still very impressed for a ported 15. For the money I don't think they can be beat, but be ready to give them alot of power and upgrade your electrical system to meet the demands of the amp, including alternators and good deep cycle batteries. I have heard these on a weak and power-exaggerated amp with no electrical upgrades and they were not doing well at all. Very good subs if you give them what they need without cutting corners.