I did buy my X1 in France at the local dealer, best advice I can give is haggle! We went back over a few days with quotes from the web and even from another dealer in the same city. We also got some extras thrown in, I think the poor girl was fed up by the time we had finished but it was haggling.
If you've been in France for a few years then you'll know you need to drive the deal, and don't take no for an answer. You can sometimes get a better deal in the smaller dealers a little way out of the cities. I'm also told by my French work colleagues that (supposedly) there are better deals in Paris (but I can't vouch for that one).
In all we got something like a 17% discount on the price (if you include the extras thrown in).
Bon chance!