I had a cap-cell from SE that I had to replace with this since it burned out after a week of use. First off, I have enough packaging peanuts to last a lifetime now since the battery was buried in a box about 100 times it's size. Definitely better than finding a lead & acid surprise. The machine screws sent with the battery weren't long enough to accommodate my Monster ring terminals, but 50¢ at the hardware store fixed that. As with the cap-cell, I have no headlight dimming. Finally, the thing that really matters, SPL. Since the only difference in my system is the loss of the "600 W Cap-Cell", exchanging it for this "20 AH Power Cell". To be honest, despite the cap-cell having to work when the subs were brand new and not broken in, my system had more pop with the cap-cell. Maybe adding a capacitor will help.