I am looking for my first handgun. My first firearm, actually. I want top-notch quality, and price is irrelevant. I live in California, so I assume that my options are severely crippled, but I intend to buy one anyway. My girlfriend and I recently had a break-in experience, and I felt extremely vulnerable. Things would've gone a lot differently if I had been armed. I want to be able to protect her from harm. I want the best of the best of the best.

This would be for home defense, so .45 ACP seems to be the most realistic caliber choice. More specifically, I was thinking about Remington Golden Saber HPJ, because I've heard great things about its penetration/weight retention/cavity size. Handgun Ammunition - Golden Saber HPJ Ammunition

As for the handgun itself, the HK45 was almost selected as the U.S. Armed Forces' new sidearm, but the Joint Combat Pistol Program was unfortunately canceled. It was their first choice, though, and its ergonomics/reliability/accuracy look incredible. It's been quoted to be the 21st Century 1911. Heckler & Koch - USA

Since the HK45 has a rail on it, I was also considering buying a Laser Sight/Tactical Light, since this would be playing the role of house protector. The best one I could find was the Viridian C5L. Viridian C5L Gun Laser Sights | Viridian Green Laser Gun Sights | Glock P22 Ruger Sig Springfield XD

I would really, really appreciate some help from you gentlemen. This stood out from other forums because it's specialized, as I'm sure most of you are. If you have any information regarding home defense, I would really appreciate it.