[DivByZero]

Thanks for the comment. Great considerations.

Totally agree that overall Facebook Ads is great for demand generation while Google Adwords is much better for demand fulfillment. Also you're right on the attribution model, Facebook clearly attribute to itself every conversion from people who clicked the ad no matter of the last click.

In the future I'll try to make a followup post playing with GA various attribution models and checking how they change the data!