I also run a calculated 11:1 in my daily driven 73 Nova. Its a 350, RR200 Brodix heads and the works to be short about it. And i could probably actually get away with 87 octane if i kept off it. Ive done 90 before and had not a sign of any detonation even under load when it was 90 some degrees out. I completely know the DCR factor. But if this isnt a car going for every last little hundreth then i say its not a big deal. My DCR is in the mid 7's and my car to say nicely is no pooch. Ill get some numbers for ya this spring/summer. If i had another half point of DCR i doubt it would make the world of difference ya know. What are we talking about there maybe 2% increase? My neighbor runs that same generic cam with an 8:1 truck 350, with old crap smog heads in his wifes camaro and the car is pretty quick, and sounds great, he thinks with tuning and such it would go 13's, so i can only assume that with 9.5:1 it wouldnt be bad. My point is if the motors together then 9.5:1 would be fine. sure 10:1 even 10.5:1 would yeild you some more power but at the sacrifice of running 89 gas and possible detonation in bad circumstances. Its your call.