Try a 'colored' food like beets. That is a good indicator of transit time for me. When my mouth sees the beets advancing I swear it's out the other end before they even hit the chompers. And it's so easy to tell transit time with beets because the first time you try them you pass out because you swear you've just hemorrhaged every drop of blood in your body. After you wake up from passing out you'll then remember that you had beets and you're perfectly fine. But the color in the toilet is absolutely awesome!
kathy