I think what you guys are liking is the extra tube distortion it can add as a result of depriving the toob of the necessary voltage, etc.
A hybrid design does kind of make sense for that app, when you think of it. The solid-state portion is probably going to respond quicker to transient-y stuff like a snare -- while the toob portion can add a little grit without otherwise mucking things up too bad.
I have a hunch that the Aphex 107 or 207 might make for an interesting snare color, as well -- though I have yet to try it.