Yes, the Guide is very good and thorough. I've found all its advice to be sound, and when taken, successful. One does not need to use any particular product, or indeed any "product" at all, to use it. Though they do make it easy for us. A large number of riders use Endurolytes, as the cost is small compared to the benefit. Hammer Gel in the flask is probably the next most common product of theirs that I see.