Bobby Gately’s recommendation is another grand slam! I was running 4 Gately Shield 8’s 4 ohm on a Sundown SFB 3000. Sub’s sounded great and hit hard in my single cab truck. But the clip light was going nuts at roughly 10% gain. I called and talked directly to Bobby and he told me to run the Ruthless at 0.5 ohm on them. BOOM WAS HE RIGHT! Only thing I wish the Ruthless had an internal cooling fan. It has not turned off due to thermal protection but it has gotten warm to the touch. So I am adding an external cooling fan over the weekend.