The P220 has an 8 rd mag unless you get a 10 rd extended mag.Â* The P99 has a 12 rd mag normally, but in CA a 10 rd mag as I understand.Â* So capacity really comes down to 8+1 or 10+1.
I have handled the P99 and liked it although I have not yet had the opportunity to shoot one.Â* If I were looking at a P99 I would also be checking out the new Springfield Arms XD(M) for a side by side comparison as there appear to be some ergonomic similarities and they are both .40 cal.
I have only shot one older P220 but much enjoyed it.Â* But then I have liked every P series Sig I have ever had the opportunity to handle or shoot.Â* I am a big proponent of ergonomics on picking a firearm.Â* The more I shoot and learn, the more I am interested in:
1) How does it fit my hand in general
2) Can I easily reach all controls present - safeties, mag release, decocker, hammer, trigger
3)Â* Does it sight naturally in my hand, ie if I just pick it up or draw it from a holster and point it without adjusting my grip are my sights aligned, does it feel good
4) Balance which is hard to determine as you typically don't have an opportunity to handle the firearm with a full magazine while shopping.
5) Natural feel over all - does it feel good in my hand, is anything poking me or rubbing on my palm or web of my thumb, does the trigger fall naturally to my finger or do I have to reach for it or overly bend my finger to shoot.
IMO buying a gun is a lot like buying a pair of shoes.Â* There are 2 things you need to figure out generally 1) is it appropriate for the purpose - you don't buy penny loafers to go jogging and you don't wear your featherlight jogging shoes to go hiking in rough terrain 2) do they fit and feel comfortable.Â*Â* While looks or branding play a role, it makes no sense to buy the best looking shoes or handgun or the most popular brand if uncomfortable or painful to wear/use because eventually you will just throw them in the closet and be done with it.Â*
I find choosing a sidearm is a very personal decision.Â* You can read all the gun mags, reviews, forum comments, etc but YOU are the one who has to carry it, YOU are the one who has to field strip it, YOU are the one who has to clean it, YOU are the one who will have to shoot and train with it and it is YOUR life or the life of your loved ones it may save one day.Â* After reading and listening to opinions you need to go to a store where you can handle your final choices side by side, make final comparisons and make your final decision.Â* Just my thoughts on it.