The people that blend these oil get paid to get the oil to pass API specs. If they do too good of a job, it must cost more in some way to produce the oil. I'll bet they just meet the specs and stop right there. There must be a lot of different ways to get there, but no reason to be any better. The oils will be different but the results are probably the same. Just give it up and pick one, cheapest price will work, for a selection method. In California, with cupons, Chevron can be had for as little as 57 cents a quart, otherwise you might pay a buck or so. Both are good oils, no wrong choice here.
And don't put too much into someones one off uoa. You can't know enough about the vehicle condition, driving conditions and oil chemistry to make a decision on what you should use. I'll bet there is not a bad API oil on the market, not even in your grocery store.