I've consumed a lot of energy bars in my day (training for marathons etc). In my experience the most important thing about eating energy bars is variety. If you have to consume any significant quantity of one type of bar your enjoyment of the trip is going to go down. I can eat one cliff bar or one power bar a day, not more. And if I have to be eating them again tomorrow then I want to switch both flavors and brands. Why brands? Because all bars from the same brand have pretty much the same texture and that gets tiresome.

The latest new thing is probar. I tried one the other day and they taste good and have every indication of being more nutritious because they are not baked. They are essentially fruits and nuts pressed together into a bar. Since they are less processed I would guess that they are better for me. But they are not cheap and at the end of the day you have to ask yourself, "gee, why don't I just pack the dried fruits and nuts myself?".

Here's another thing to consider. Different energy bars are designed for different purposes. Power bars, for instance, are aimed at distance runners who are running out of energy during a long race. As a result they are mostly carbs, not the simplest carbs (pure sugar) but a slightly more complex carb made from rice. Other bars like the probar have lots of nuts which means fats and proteins. Now you need all three to hike: carbs, fats, and proteins. But they digest differently. If you need to fuel up quick you need a high carb bar. So I might eat a power bar when I begin to feel shaky because that will get sugars to my muscles quickly. If I eat a bar with more fats like a probar then I will need some time for it to digest.

Does that help?