Been gigging "two" Mesa M-6 Carbine heads for awhile now, absolutely LOVE them. One of them decided to blow it's power section recently, (the other one has been rebuilt/up-graded by Mesa and is doing fine.) I took the blown one to my closest, authorized, certified, Mesa Service Center and was told, "They DON'T service M-6's or M-9's at local Mesa Service Centers, they have to be returned to Mesa in Calif." .... (Something to consider if your thinking of picking-up a Carbine while their still available.) I'm not sure I really want to put shipping charges and even more money into these heads. I'm keeping my working M-6 and will to continue to gig with it for as long as it'll last, but I'm looking for recommendations for another head that will have that feeling of power and speed with the absolute clean low end, the bell like chime of the attack of the note, and the clarity, clarity, clarity of the M-6. I've heard it said here at T.B. that a Glock head would be a near replacement, but I've never even seen one let alone played through one. Some say the M-6 was Mesa's answer to the clean G.K. sound. I've a G.K. MB-500 that I'm using as a back-up right now, and the MB-500 compaired to the M-6, it's no contest. To my ears, the G.K. seems to have a blanket over the cabinet in comparison. Looking for any and all recommendations for a head with the above M-6 attributes.