Hi,
I struggle to eat in long runs, but for the real biggies I find that I have to eat. Relying on drinks alone is ok for marathon distance, but if you are running for 10 hours or more fluids alone just do not cut it.
I always find that it is just a question of what you can keep down. A little and often is the only way for me even if it is just a bite of food every mile or so. I do use energy drinks as well occasionally, but tend to stick with Nuun mainly.
Some of my favourite food on the go are pringles (salt and vinegar), frozen mini mars bars, small Mr Kipling cakes (two pack), skittles, Red Bull mixed in with Nuun, Bananas - Yes all rubbish food apart from the bananas
Ultimately I think that most long runs tend to be miserable until you cross the line, then everything ceases up. Trying to eat when you are exhausted, dehydrated and when it is warm weather is really hard to do.
Anyway, good luck with your long runs.
Trev.