Default [Q] Traveling to Paris, France and voice/data question?

All,

Traveling to Paris France for 10 days. I have the ATT LG G3. Got a couple of questions:

- Their international roaming worth it? 120mb for $30 or 300mb for $60
- Can I unlock the phone from ATT? Or should I go through those phone unlcok sites?
- Anyone know of good France carriers that will give me LTE via prepaid SIM?


Thanks for all your info!