Ya, some of the high end units like the old Control 24 have Focusrite Pre's in them.... I'm pretty sure the 002/003/11Rack stuff does not, but of course I could be wrong. I figure they would be bragging about having Focusrite Pre's in all of their units if they were there.
I wish I could get my hands on some Digi schematics so I could see for myself what's going on in the Analog stages.....