I did a 10-mile race, not really racing, just for practice drinking water from aid stations. (And as I said before, a flat place to do my long run was nice, too.)
First station: came to a complete stop but forgot to get my breathing sorted. Even though my HR wasn't very high so early in the race, air in my stomach, water up my nose, water down my windpipe. 
Second station: a little better. Walked through. But I'd taken a swig from my gel flask, hoping to wash it down with water, and didn't do it far enough in advance. Gel up my nose. 
After that it was pretty much okay. I wasn't sure whether I should stop at the last station at mile 9. Should I just press on for the last mile? I stopped, but only for half a cup of water, and the rest I poured over my head and back.
I realized that I'm out of practice gulping from cups, at all. I drink water all day from my Camelbak bottle. Cycling I usually use ordinary squeeze bottles, for training runs I use a pack with a bite valve. The only beverages I drink from cups are either hot or alcoholic - both sipped. Maybe some cup-gulping practice is in order. 
It was hotter than I've been training in, but since I've been tending to train in the warmest part of the day, whereas the race was first thing in the morning, I never felt overheated. Drenched, literally drenched with sweat by mile 6, but never overheated. And I must've been well enough hydrated, since sweat was dripping off me pretty profusely when I stretched afterward.
There were only 150 runners. It seemed like a light turnout for as well organized as the event was, but as my first race over 5K and my first race in this area, I have no idea what kind of turnout they usually get. I overheard someone saying the temperature might've kept people away.
I finished in 1:37:51 (@9:48), which I'm more than happy with, considering that I really wasn't intending to "race." GPS says I kicked the last mile @8:41. 11th of 29 in AG, top half overall.
Most of it was on a MUP, which wasn't closed but had very little traffic other than the race. It was a pleasant setting in the midst of suburban wasteland, with more shade than I'd expected. Coolest thing about the race: by half distance, the shiny sealant on the path surface was covered with droplets of sweat, exactly as it would be in the beginning of a light rainfall. Good fun.
Speed comes from what you put behind you. - Judi Ketteler