I've got the 9/15 and am digging it. I use it with Fred's 2X12 F Cab with a Blue and a 70th Anniversary G12H30. Although, most folks seem to like the 6V6 side, I only use the EL84s. For home use I run it with a Bad Cat Leash attenuator most of the time. I've got a crazy pedalboard and use it alot with my Tele. Anyway, I've been wondering if the RSA 31 might be better for me but I've heard it is really really loud. Stu at Fat Sound told me it was louder than most AC30s for sure. I asked Fred what he thought about running it at at 1/2 power most of the time and he thought it was kinda pointless to have an amp that powerful and not use it to it's full potential. It seems like it might be too much for me. What about using it with an attenuator? I'd also like thoughts on the tonal differenced between the two amps. Thanks!!