What should I know about the French Foreign Legion before joining? What are the benefits and drawbacks of being a legionnaire?

Have a decent lunch before you walk through the gate and spend a few days in a hotel in Aubagne on your own to think hard and well before you give up your passport. It takes guts to give up everything and walk into the unknown but its also a great adventure. Legion progression is quite slow compared to serving in your own country, which can be frustrating if you got your head switched on and would like to progress quicker. You must learn french as fast as possible which is a major hurdle. After basic when you arrive in regiment the first 18 months will be spent doing a tonne of cleaning and extra duties. Forget having time for breakfast in the morning and having to speed eat lunch so you can get your afternoon corvee finished for review. After 18 months it starts to get easier, you do less duties because other new guys have arrived in your section and the corporals have shifted their focus away from you onto the fresh meat. At around 18 months you will start being groomed for corporal if your french is at a reasonable level. Its all peace and love once you manage corporal (which can be made within two years of service). If you want to do it, just go do it, it will toughen you up and you will have a great story to tell the grand kids. Its a job and career if you want it to be. Then again seriously consider your own army first, learning french was a real pain in the neck. I hope I helped!