Hiya Magnus,
From my past experiences with dev-internal questions, I found Paul was faster to respond on the google-groups site:
https://groups.google.com/forum/#!forum/c65gs-development
I'm guessing it's because he's getting email notifications there, but not on this forum site (so he only visits this forum site once in a while?).
So just thought I'd mention it, in-case you want to drop your Q there too.
Yeah, a 400MHz 8-bit machine sounds awesome. I remember reading an interview in Commodore Free where Paul has a 'secret' plan to fabricate the final chip and make it 10GHz, holy moly !!! :D
http://www.commodorefree.com/magazine/vol8/issue82.html
...but it's a secret, so shhhhh, don't tell anybody ;)
Gurce