I use regular Gatorade in powder. I have found it is the best thirst quencher, and the sugar does provide a quick energy boost, along with some electrolytes in the sodium etc. However, it is not the best endurance drink. For long term energy needs, I just rely on taking along a few easily digestible energy bars. The kind that don't have big globs of oats etc, but are processed so they dissolve and digest more quickly. I have found personally, the PowerBar Protein bars work pretty good for me (cheap too). I take those along with Gatorade as a thirst quencher. Those two seem to be a good combo for me, but everyone is differant.

All you can do is experiment a bit till you find what you enjoy eating, and what works best for your performance needs to boot.