On a well maintained car, this really shouldnt matter.
I would venture to guess that most engines that fail due to forced induction would be the result of one of three things:
1)Abuse
2)Poor tune
3)Too much power for stock engine
IMO, a good tune with a driver that doesnt beat the snot out of their car, and MODERATE power levels and a stock bottom end should last a long time.
Cant remember where, but I did read on a forum where a guy had a blower on an NPI motor, maybe 9psi...he supercharged at around 100k, and had upwards of 300k on the motor, all stock and from the factory.