What is the best holster for a concealed carry 9mm Taurus PT709SS Slim?

I'm currently using an Uncle Mike's pancake size 15. Should it be a size 16? Any other options(perhaps leather or molded)? I'm not a "cowboy" or "vigilante" but a retired US ARMY SFC. I served my country with a rifle for 20 years. Now I protect myself and others by being a licensed CCW holder. Thanks,