I make my own, reusing old Gatorade containers. Like captnfantastic I usually drink it only after the first hour, or on a long ride over 2-3 hours I start drinking at the beginning. I mix 3 scoups into a 24oz bottle, which is about 225 calories, and drink 1 bottle/hour. It's really easy to make and has been a lot cheaper than buying it. Plus you can customize it to get the right balance of flavor and saltyness that work well for you over a long ride. Most of the commercial ones get old quick after about 2 bottles and my system revolts.
Here's the recipe:
1 1/8 cup sugar
3/4 tsp sea salt
1/4 tsp No Salt (potassium chloride)
1 envelope unsweetened Kool-Aid
Try the Ice Blue Rasperry or Orange flavor - they are pretty easy to drink
