Another member essentially asked the same question recently in relation to KASL and NY style doughs, and I gave him the following reply which I excerpted from my response:
My preference among high-gluten flours is the KASL flour. But there are many other brands of high-gluten flour that can be used to make NY style doughs. Whether it is worth the price and the hassle to get KASL is a personal decision that one has to make. But since this question comes up time and again on this forum, I would like to suggest that one way to approach the matter of high-gluten flours is as follows: Start with bread flour to make your pizza dough. If you are satisfied, then that ends the matter. If you still aren’t satisfied, you can try adding VWG to the bread flour. (I can tell you how to do this if you choose that route). If you try the VWG/bread flour combination and you like it, then you need not look further. If you don’t like the VWG/bread flour approach, then you can try to find high-gluten flour. Since you won’t find high-gluten flour in the supermarkets, you will have to look for another source. It might be a distributor, a foodservice company, or it might be one of the big box stores like Costco’s. Depending on the source, the high-gluten flour might be KASL, All Trumps, Bouncer, ConAgra, Pendleton, or whatever. They will all work to make a NY style dough. What will usually dictate what you buy will be availability in your area and price. In most cases, however, you will be buying a 25-50 lb. bag of flour. One advantage of the KASL, if it matters to you, is that it is unbleached, and non-bromated. It also has a higher protein content, 14.2%, than just about all competing brands. Whether that matters is again a matter of personal choice.