Seems like this question comes up every year -- not sure whether you can check the archives, seems like they're down?
Anyways, you *can* run it at 75cfs, but it's pretty bony. I did so a few years back, still had a good time, but running class V creeks isn't my forte. I also ran it at 250, and it was very fast and pushy -- no eddies, had to remember all three gorges from a scout. Ran the 3+ miles in under 20 minutes. Very fast...
If you want to get an idea of what it looked like, I have some pictures on my site -- although it was too fast to take many.
I think that most people wouldn't consider running it under 150cfs or so... if I remember past discussions. Hope this helps,