umstud - I can't remember if the Limited version of the P-16 has an ambi safety, but if not, you might consider one for IPSC. Get as many hi-cap mags you can afford for it as well. If you plan to use it strictly as your IPSC gun and don't plan to keep it loaded in the house or carry it, have the grip safety altered so it doesn't work. None of my competition guns grip safeties will work. Every serious shooter I have met has had their grip safety deactivated because it sometimes causes problems. For more info on this discuss it with the better IPSC shooters in your area.
Welcome to the sport, it's a lot of fun.