I carry a Wilson CQB/rail whenever I'm not working. The gun is about 6 years old, has about 25K through it, and runs like a scalded dog. It still shoots better than I do (I can hear the wisecracks now...). The only parts I've replaced are buffer springs and shok-buffs. It was a nice tax deduction
I like Nighthawk as well, and will likely own one. They're a newer company, that's true. But they were started by former Wilson 'smiths, so there's a fair bit of experience there.
If I had to choose between the two, I'd pick the one closest to my hand or perhaps the one the dealer priced a bit cheaper.
I can tell you that Wilson customer service was excellent when I ordered the pistol and whenever I called them for anything.