Depends on what you like foodwise - I've tried sports beans, would think peanut butter would be harder to deal with, and would not act as fast as the others if you needed a BG boost. I think if you check while running you'd learn some things about what your body is doing on the longer runs especially. Body may be looking for another boost of carbs after an hour or so - something else to burn for fuel. Dexcom is something that helps with monitoring blood sugars as well - able to see trends before, during, and after (which is another important area to watch - recovery is something that is easy to overlook, and after effects can show up hours later).
