I have 2 of these and another buddy of mine also has one.
I have the HD 135 head and run it into a Psychedelic Liberator from Hard Truckers and it kills. This is my main amp because it is easy to move around.
I also have the HD 135 with 4- 10 inch speakers. this mother is heavy, really heavy. Johnny Winter actually played it for a gig at our place. He has been using Music Man amps for years.
Clapton played one for a long time and I remember Weir used one for a while around '75 I think. Knopler also
These are killer amps> I usually play it clean with an Ibanez Tube Screamer when I want to dirty it up. Lots of fun........