Franci:
Here is what Rose Levy Berenbaum published about the widely available commercial flours in The Bread Bible (a book that I think got really very mixed reviews here on eG when it came out, but one that I rather love):
Gold Medal unbleached AP: 10-12%, usually 10.5%
Gold Medal bread flour: 12.1 to 12.6%, usually 12.3%
Pillsbury unbleached AP: 10.5-11.5%
Pillsbury bread flour: 11.5-12.5%
King Arthur Flour (KAF) high-gluten flour (also known as "Sir Lancelot): 14%
KAF bread flour: 12.7%
KAF AP: 11.7%
KAF whole wheat flour: 14%
KAF white whole wheat flour: 13%
KAF Italian-style flour: 7.4%
KAF European-style Artisan flour (this one might have a new name): 11.7%
KAF French-style flour: 11.5%
KAF organic flour: 11.7%
I know that people do sub KAF all-purpose for bread flour, and don't always like KAF all-purpose as compared with other AP flours. That said, KAF's reputation is for consistency across the seasons.
I personally use Gold Medal unbleached AP, and KAF bread flour. I like KAF cake flour (not mentioned above), but don't have a need for it often; I strongly prefer White Lily bleached (mentioned upthread) for biscuits and that sort of thing. And I really don't like the KAF Italian-style flour, and instead strongly prefer the imported-but-otherwise-ordinary 00 flours that aren't that hard to find in NYC, when I'm trying to make super-soft pasta. KAF "Italian-style" might be more for pizza than pasta, but I can't stand it.
