I have been running a Wollf comp. spring kit (lightened striker spring, lightened plunger spring, heavier trigger spring) and a 13 lb recoil spring in IDPA out of a glock 17. 3500 rounds so far and not a malfunction. This combination is with a 147 gr.Berry's plated and a power factor of 137,000. I am considering running this combination out of a G-21 with 230gr. Berry's and a light power factor say about 171,000. Anyone using this combo? Any suggestions?