I have a CQB I like really well. That being said, their best gun, according to them, is the Tactical Elite. Aside from a heavy cone barrel and some better parts, I don't know what makes this gun that much better or more expensive. Both are rated at the same 1" accuracy to 25 yards using any of the ammos Wilson suggests.
Based on my limited knowledge of Wilson, your carry needs and some finish issues, I'd say the KZ is "best" for carry. It's lighter, "skinnier", higher capacity, and probably more resistant to your sweaty, goat-smellin' torso!
That being said, I'm getting a stainless Protector. Why? No MIM parts and classic good looks (much like it's soon-to-be owner!
I'd say that the CQB and Protector lines are best suited for this purpose "out of the box" -- but then I've never had any problems while carrying a Classic, so it really is a matter of personal choice. All are worthy contenders in my book.