D600 better at low light AF than D700 (?)

With all the demeaning talk about the D600, not to mention the dust/oil problem, I was just a tad apprehensive when I took my new D600 along for a wedding gig this last weekend. My main camera was the D700, which I have always been very pleased with, and as the D600 is very new and I haven't had time to rigourously get to know it yet, I expected to use the D700 where the shots had to be made, and keep the younger brother for the more casual stuff.

In the end, 2/3 of my pictures were taken with the D600. As the evening grew darker, I actually ditched my beloved D700 in favour of the D600. "Why?!", you scream in agonized voices. AF. I was at f1.4 or f2.8 with ISO 10000 and my D700 struggled a bit, as I expected it to do, it was DARK. But not the D600. Sure, it hesitated for a second or two now and then, but mostly, it just locked focus straight away and I had the shot. I was absolutely amazed at how incredibly well it performed in the very low, tungsten light. Also, I fell in love with the muted sound of its shutter. Compared to the D600 the D700 sounded like a gunshot in the quiet church.

As I sift through the pictures from the day, I'm finding myself occupied with the less than holy thought of actually saying goodbye to my dear friend D700 and getting myself another D600. I am blown away to say the least.

Has anyone else noticed the same thing regarding the AF? That the D600 might actually be better in low light than the legendary D700? I still have this feeling that this just can't be right.
I only use the center AF-point, focus and recompose. With the D700 I switch to AF-C when there's movement, like the first dance, but with the D600 I could easily lock target with AF-S. I have also used a rented D800 for a couple of gigs in the past months, and I did not notice any clear difference between the D700 and the D800 regarding AF, even if people kept saying how much better the D800 would and should perform. I actually struggled more with it than with the D700. I told this to the people I rented it from, asked if I was just imagining this (I'm not a techy and can feel quite apprehensive about talking technical stuff), but they called it bull$hit and lectured me about how the D800 was superior in every way, and that I really should read the manual (which I had). Sure, the quality of images was amazing, but I was just less than impressed with the AF.

Hence my absolute amazement of the performance of the D600.

Yes, I have some dust/oil/whatever, had it right after a couple of dozens shots, but the spots have not increased since (+3000 now) and only show up at f16 when shooting a white surface, something I never do in real life. I'll just bring it in for a cleaning before the warranty expires and be done with it.

I am going to miss the max shutter speed of 1/8000 (often shoot my primes wide open), but other than that, I'm completely and utterly sold on the D600.

Just wanted to tell you that, bring in some positive vibes, :).