I just received today my XPS 13, if I had know all this problem, I wouldn't have bought it. Also, I'm in france and I don't speak the language, so trying to talk to the IT guy was going to be a nightmare.
Anyway, I did what you said, with the driver 6205 and so far it has worked for me. Only I see it's a little more slow, but it's stable.
So we'll see how it goes, otherwise I'm asking for a refund (in Français, wish me luck).