Student photographer here: D600 max flash sync speed?

Hey all,

I'm an artist, but new to photography.  I'm looking into buying a camera and really like the idea of a full frame sensor.  The D600 is very appealing for many reasons including the price, but one thing that I'd like to learn more about before deciding is this "issue" I keep reading about with the max flash sync speed  of 1/200.

Does this also apply to a max flash sync speed with an external flash?  A friend of mine owns the D300s and claims it can do 1/8000 with the external flash, but I read it has a max of 1/320 - so I'm a bit confused, but also hopeful that there is something similar going on with these complaints of the D600 - so what's the deal?

Am I really SOL for outdoor ambient photos with flash?  What other scenarios demand a HSS?

Also, on a side note, it seems that the auto focus on the D600 for video is fairly useless for scenes where you'd like to follow subjects at varying distances, while moving, which is something I plan to shoot.  I wonder if this could be done manually with practice?

Ok I guess that's a bit much for now, but I appreciate any advice and feedback the dpr community can provide.

Best,

cvs