My mate was wanting one BAD when he saw them announced by Marshall yesterday until I pointed out that he could get a JCM800 1959 head for a fraction of the price that would be much better built and sound like the real deal.
I'm thinking that the cascaded gain stages will be some kind of variation on a 2203. Will know for sure once I hear one.
btw, cacaded gainstages are generally hooked up with a cap tapped off the anode and fed into the next triode's grid (in very simple terms).
if you hooked up the anodes and cathodes, you'll be parallelling the stages which gives slightly more gain, but nowhere near as much as cascading (i.e. stages in series)