So getting on with the program:

Cytomax: Used it for years, but it has to be full strength to even begin to keep up with energy expenditures. Full strength meant I couldn't back off when I got sloshy belly, which caused me to almost bonk a couple of times. Plus it paid for about 1/5 of my dentist's new Mercedes.

Gatorade: Tastes nasty to me, so I couldn't drink enough of it. Maybe because of that, or maybe because of its formulation, I seemed to go slowly downhill with it.

HEED: It's OK. Much better in the mouth than the first two. At a strength/flavor I can tolerate, it doesn't keep up with energy expenditures but it's good otherwise.

Endurolytes: With these, I use maltodextrin + whey protein: Great for energy, no electrolytes, hence the Endurolytes. Spiz, Accelerade, Sustained Energy, and Perpetuem fall into this category. When riding hard, I found I prefer to separate the three nutrients: water, food, electrolytes. This is maximum silly for touring, but you could use Ensure or Ensure Plus. Put half a dozen bottles in your bar bag and ride for 10 hours on them. Still pretty silly, but something to consider if you think you'll have to dry camp or have a desert to cross. Drink a bottle in the morning and you're off.