SIM Card at CDG or Paris
 

Going to Paris on Sept 11. I found an unlocked phone and would like to try using a SIM Card. I have Verizon and can use the Travel Pass option, but would like to try a SIM Card just for maps. My wife and I will turn off roaming and only use WIFI when available.
We will be there 8 days.
Should I buy one in CDG when we land or wait and buy in the city?
What is the best one to get and where? We are staying in the 11th.

I have monthly service, so I do not keep up with the numerous prepaid plans which are constantly changing. Little to be gained by taking time at CDG to find a SIM. I would go to any of the major player boutiques in Paris; Bouygues, SFR, FREE, or Orange. Have them explain their plans and install the SIM. They can make sure it woulds as it should.