[quote=The Nexerus]
Michael's was the most successful.Why the hell did he jump out of the boat at the end, though? He must've known it wasn't the one rigged to explode, because he'd saw the rigged one explode already. If Geoff had any sense he'd have shot Michael when he was in the water.
[/quote]

He was probably unsure of who rigged that boat to exploded and was probably sure that Lindsay rigged their current boat to explode. 

As for Geoff, it does depend on who had the heist money at the time. Killing someone in the water with it would have caused the money to sink, never being found again.