When we bought our house and proudly showed our french friends around , they quickly pointed out all the negative aspects .. "Oh lala , you'll have to change the tiles here, they are so passé ma chérie" ... " Well, that bathroom needs to be ripped out for sure" " Surely you will not be keeping the crazy paving on the terrasse?" etc etc... as we grimaced and led them through to the kitchen ( very ugly) for some appertifs ( we must give you some recipes ma petite...) our house was verbally ripped to shreds!
The French are the first to tell you that you've put on weight ( my beautician, just after I'd given birth to second child), that your ears stick out ( dentist), that you haven't a clue how to cook/bake/sew/bring up your children as well as they can, and of course that you cannot speak french properly ...
So when you do get a compliment from the French , lap it up and savour it , turn it around and examine it from every angle .. because a) you may not get another one and b) you can be sure they are not lying!
Honesty , the best policy? Perhaps yes, but a little tactfulness goes a long way. You're looking great by the way, have you lost weight recently?!!