Strictly speaking your good for holiday cover only,I found 1 company that gave 18o days but its a grey area.
Most ignore it and take a chance but there are some horror stories when it goes wrong.
If you import your car as your meant to then there is an import tax related to age and horse power i think.
http://europa.eu/youreurope/citizens/vehicles/registration/taxes/index_en.htm
Its not that hard to import you need a french MOT CT its called and go to the tax office for a document to find out about tax, change headlights before CT and you will need a certificate of conformity from the manufacturer some charge some dont Fiat charged me 170 euro for a Ducato mitsubishi gave me one for free as did Honda,crazy!
Insurance here is far cheaper and you can bring your no claims.