I too made a pair of chaps out of driducks rainpants. They work fine, and indeed, a single chap-at-a-time is a lot easier to put on and take off than a pair of rain pants, at least rain pants that don't have side zips. And those tend to be heavy.
I don't tend to wear chaps when I'm walking, however; unless it's pretty darned windy, cold, or particularly windy AND cold, wearing any sort of rain pants or chaps when I walk just means I get wet from the inside out (perspiration) rather than the outside in.
Of course a drawback of chaps for in-camp use is that your butt isn't covered if you sit down!
I probably use my chaps most often for just starting out on a wet morning, when dew or raindrops are on the vegetation. After both external temps and I warm up, off they come.