Well, I'm actually trying to measure how much force I can get from servos for a plane I'm building. Under the current setup, the plane's tail will hit the piezoresistor vertically, and this in turn goes to the adc since I want to log all the information. My first thought was to go with the piezo right away, but now I will research everything you mentioned, Mark.
Terry, the servos output around 6 kg*cm. Like I said, since I'm just starting the research in order to build the test stand, pretty much everything goes.