Overdrive doesn't necessarily mean grindy, grainy, or snarly either. Some of my fave stuff is smooth and creamy and detailed in the lower-mids and mid-mids while having nice sparkle in the upper mids. And a lot of that is because of pre-tube and post-tube EQ contouring.
+1 to all these posts. My point (based on Roger's info in this thread and others today) is that the design goal of this head does not seem at all the more typical hybrid design of putting a single 12AX7 in the signal chain for a little more tube warmth in an otherwise solid state voiced amp (like the Shuttle amps). This seems to be going more the Mesa MPulse and especially the SVT7PRO direction of really trying to cop a 100% tube amp vibe, tone and feel, which of course can be very clean or snarly as heck. However, even the clean mode, I would guess, would sound quite different than the Shuttle (which is again what Roger is implying if I'm reading his comments correctly).
The beauty of this sort of design is that, unlike virtually any all tube amp I've ever played, you can keep whatever amount of 'tubiness' you dial in at a constant tone, and drive that tone, whether round and clean and airy or all out snarl, to ridiculous volume levels without those relatively low powered tube power sections really changing tone and performance as the volume increases to above very moderate levels.
IMO... makes perfect sense to me