[ChkbookMechanic]

I haven't heard about the e60 cars having the radiator / water pump problems, of course, those only showed up after 80k miles on the e39.

The water pump issues seemed to be on the E39 inline-6.
The radiator affected all E39 except the M5 which had a larger radiator.

However, the radiator and water pump wern't the worst issues, it was the mechanical fan clutch that would go out and cause the fan blades to go through the hood and into the engine block.

Looking at the new 5-series (e60) they seemed to have addressed all the engine issues such as the water pump, radiator, oil cooling and fan. If the warranty is the CPO warranty I wouldn't really count on it being worth anything given my experience w/ a CPO warranty. If it is the extend warranty the original owner bought when they bought the vehicle it is actually very good.