I have used both the reduced power and standard power ribbed mainspring without problems. The reduced power model will fiatigue faster than the standard model and you will get light primer strikes and failures to fire. You can re-arch the spring and get a little more life out of them but replacement is the real cure. I keep one of each on hand in my range box for ready replacement. I prefer the feel of Wolff's factory power rebound spring although I have used their 14# spring in the past. Just my personal preference, experiment with the various weights till you find what you like.