Vantaggi
It's an outsourcing company with all it's ups and downs. Pay would always arrive on time. Some nice people worked there in Sophia Antipolis (not among managers sadly), and at some point they had a really good agency director. These days it's just a company like any other in this business I guess. Not any better, not much worse either. On the upside I could probably mention that they really used to help foreigners a lot in moving their lives to France.
Svantaggi
It's an outsourcing firm so they'll promise you silver mountains to have You sign the contract. See some episodes of "42'ème etage" to understand how they roll in France. All true. Once You're on CDI You have 3 months notice period straight away, and You likey won't even see your salary follow inflation, let alone show some real signs of increase. Also, in no way does your salary depend on Your work's results or customer's feedback. Forget bonuses and other things outside basic pay, you may get a gift for Christmas though... in the price range of 50 euros.