I did my first successful 400K this year and the approx. 200 calories per hour in liquid form was the biggest reason I think I managed to finish it. I gave a unit of blood the week before I did it so I was handicapped by that, so the ride was a real grind. I stopped for supper and had a veggie burger with salty fries; found myself extremely thirsty and bloated. I think the salty fries did me in more than the burger, but I would only eat half the burger next time.

I did stop and get potato chips and nuts when I stopped for water just to have stuff to nibble on but most of my calories was homemade malto-soy drink, if you search the archives in this forum there are some good posts about it. It's a homemade version of hammer perpeteum. This my first season of riding brevets and switching to liquid nutrition seems to have helped make them easier for me, my first few 200K and 300K rides were done with more solid fuel and I was hurting after every meal... nevermind the 15-30 minutes every eating stop seemed to take me it's just been better for me to keep riding and get the control card signed quickly.