I haven't flown a Cessna yet but on our 70's-80's vintage PA28's it's part of our pre-flight to push the flaps to check for movement when in the fully extended position. Rarely is there more than 1 cm (.2 inches) of movement on the trailing edge. Then again the flaps on the PA28 are a rather simple "bicycle chain" style setup so I would not anticipate much sloppiness unless something was in dire need of servicing.