First, BIG ASSUMPTION: Everyone, both teams 100% healthy because obviously close to time my opinion may be colored by an injury or two.
So assuming that, I think DUKE and it has nothing to do with whom may be better at the end of the year.
K is better on adjustments than Cal and you are not even seeing two of our starters playing in Canada to have a feel for how our team will play as a unit. Duke will adjust on the fly (IMO) better than Cal which is crucial this early in the season.
Duke always seems to be better prepared than most teams early in the season, and you can't get any earlier.
I like our bench - yeah you have more depth and experience on paper, but I really like our bench.
Duke is in Cal's head and in turn will be in the players head. I think this makes for more mistakes.
Anyway, that's my opinion.