The descriptions on the Two-Rock site are fairly vague, and the clips on the Two Rock board seem to stay in the clean realm. How do you classify the various Two-Rock models? The Custom Signature 50 looks really interesting to me. Is the drive channel more of a smooth or gritty overdrive? Are the cleans supposed to be blackface style? Are the other models all iterations on the same theme, or are their amps all significantly different?