Singapore Airlines were great. They cost a bit more but they are reliable. For example when travelling to Le Tour my ticket was approx $2400, my mate was flying some low cost China Air or something like that for about $1700. His flight was supposed to leave an hr prior to mine to Paris but his flight was delayed for 12hrs inconveniencing him and his family big time. With Singapore nothing was too much for them, we had a great trip. They stop in Singapore which makes the overall trip a few hrs quicker than Emirates,Qatar etc which stop in the Middle East and so you have a longer overall time to arrival in Paris.
Check when booking to ensure you get the extra baggage allowance. I did not get charged for my bike either way. Train is a good way to travel through France. If by chance you are basing yourself in say Grenoble, you will need a car as it is too dangerous to ride out of Grenoble if you have a roadie and too far if you are on an mtb.
Don't skimp on your travel and insurance.
If roadie check out a site called Velonomad run by Tim Marsh. Whilst it is geared for roadie action, it will still be useful for mtb as his travelling info covers everything from SIM cards, accommodation, locale, training for climbing, bike bags, packing, eating on a plane etc with really inexpensive web books etc. I found his site enormously useful. He will also reply to direct email queries really quickly.
Plan, plan, plan and you will have a cracker of a trip.