At the Seattle marathon (12/30/08) I had planned to drink the Gatorade Endurance offered at the fluid stops and that's it. The only problem was that during the marathon, I grabbed a cup of Gatorade Endurance and spilled a lot of it. Somewhere around mile 15, I figured out that I had a problem and that I needed to eat something so I ate some gel. Now I'm using gels (usually Gu Espresso Love) on my long training runs since I can get all of the gel into my mouth. So far, so good.
~Gotta Run Now