5 BTC
1GCDzqmX2Cf513E8NeThNHxiYEivU1Chhe
I bet he will not pay.

This bet will be hard to settle. You have to verify that pirate:

1) paid back 100% of the borrowed principle
2) paid 100% of the promised interest
3) and paid 100% of the debt holders according to 1 & 2 above.

Unless all the books are opened...this will be tough to prove. If the books are opened, sounds like someone needs to write code to verify it all...but then there will undoubtedly be some exceptions and informal transactions, etc. it will be messy.

Many people will lie and claim they didn't get paid fairly if they can't be proven wrong...if only to win this bet.