Ruger was always good about making ambidextrous weapons. Honestly, the right handed gun thing never bothered me. For semi-autos I would use my index or middle finger to drop the mag. Use the index finger to release the slide stop, and index finger or thumb from supporting hand to activate de-cock lever or safety.
Now I shoot mostly revolvers again. There is not advantage/disadvantage for us lefties. One advantage, though, lefties use there strong hand to reload without having to turn the gun upside-down/inside out.