An uncaptured steel guide rod allows you to change recoil springs to match the ammo you are shooting. Cajun Gun Works sells them. A fiber optic front sight is helpful. I have put Frank Proctor front and rear sights on both a P-10 C and a P-10 F. However, if you are thinking of going to a red dot in the near future, adding anything other than suppressor height sights is a waste of money.