I think my hearing must be way off. I've owned an old Blueface VH4S and a 2007 VH4, and have played one of the new 2011 Blueface reissues.
I thought the early Blueface was much less gainy and much less compressed. And I actually thought it had LESS treble but MORE presence than the 2007 VH4, but maybe I just don't hear things right. VERY aggressive and pretty dry. Actually a difficult amp to play. It truly was best cranked up a bit, but once it was cranking it was pretty glorious. The 2007 and 2011 seemed about the same as each other. Gain was more saturated and it felt more compressed (for example, switching from channel 2 into channel 3, you could sorta feel the frequencies getting squished into a smaller band). Was easier to play because the notes would sustain when I was a bit sloppy (the Blueface, if you didn't hit that note right, it was gone and I looked/sounded like an idiot). And I thought it sounded more consistent from low to high volume. It lacked a raw-ness or vicious-ness compared to the Blueface (people complain that Diezel's don't cut through, that old Blueface could not be ignored). New ones seem more "polite," I thought. Maybe thumpier low end, too. This was all with the same V30 loaded Mesa cab.
EDIT: and none of these amps had external bias.
Double EDIT: they all sounded great, IMHO. If I couldn't play loud, I'd probably opt for a newer one because I did think it sounded more usable at lower volumes. If you can crank it to loud-ish drummer levels without guys complaining, then I'd opt for the old Blueface (if you could both find and afford it). They all sound like a VH4, though.