bigfred 

I have to agree with what Homeyba and vesteroid have said.

Regardless of how much larger we are and how many more calories we burn, are systems aren't designed to utilize substantially more calories per hour than anyone else.

Subsequently, eating small amounts frequently becomes very important. At least for me.

I've not been a user of the commercial products. But, that may change for this coming Novermber's Taupo Challenge.

In the past I've relied on a good breakfast of oatmeal with raisins or a mixture of corn flakes, muesli and yogurt. On the road I rely on in more or less this order: granola bar(s), banana, fruit newtons, snickers bars, gummy candies. Occassionally there might have been a pbj thrown in there. My principle has been to work from the slightly more complex energy in the granola bar and banana toward simpler sugars near the end, culminating in gummy candies.

With regard to hydration: I tend to not like full strength sports drinks. So, I start with one bottle of water and one of approximately 50% dilute sport drink. I'll carry one sachet of sport powder which will be good for two additional bottles. I attempt to maintain the classic minimum of 1 bottle per hour.