I have the head version of the XXX. For high gain, you just can't beat it. I have also been fairly impressed with the clean channel. If metal is your thing, then defanately look into the XXX. The 5150 might be slightly more versatile as far as coaxing various tones from the amp, but I can get a fairly decent 80's hard rock tone to all out brutal, make you wanna break stuff, high gain tones from the XXX.