Just because you CAN run them to 8000 hours doesn't mean they WILL keep running until 8000 hours.
Also, I seem to recall that the overhaul cost of a MORE engine is higher (and the core value lower) since there are more parts that are worn out.
Pay for it now or pay for it later...
NEVER buy a plane that is already on the MORE program. It's lipstick on a pig. If you buy it, pucker up!