Yeah, I used to use one - still have it as well! It was the only way I could record my cranked non-Master amp without killing myself and anyone in the house. I had mine in a closet across from my control room and with the closet door closed, it was like moderate TV volume outside the door, however, the walls would still shake!
These recordings are all my old Mojave PeaceMaker head cranked to the max. I had a Mojave 4x12 with G12H30s in it and the mics were SM57s.
On these, lead guitars were recorded in the ISO Box: