A few days ago, I installed a Scumback H-55 into my Carr Slant 6V. I really liked the amp stock, but I felt that the Kingpin 60 leaned more toward the Fender side of the tonal camp, and I lean more toward the Marshall side. I read about Jim's speakers for the first time on this forum (thanks everyone!) and took the plunge a few weeks ago. Jim couldn't have been more friendly and helpful, both in emails and on the phone, and I couldn't be more pleased with the speaker. The amp's clean channel still is gorgeous, but a little warmer sounding than the Kingpin; still, the channel shimmers up there with the best of them. The lead channel, though, has taken on a more aggressive, more 3-D tone and feel that is so rewarding, so satisfying. I went with the 30-watt version of the speaker; I never get to push the amp much beyond halfway anyway, and if I ever get to, I have ohmage-matched 1x12 extension cab that will let me turn the volume all the way up. Again, I wanted to thank folks here for some illuminating reviews as well Jim (and Ted Weber) for such a great speaker...I will be buying more for other amps!