Buying a Magnum Core- Max Mileage?

Guys, I have tuned hundreds of Magnums and the motors are stout. I would have no qualms about spraying or boosting a motor with 150k on it.

I have seen some issues with guys scoring bearings, but i think that is from shoddy maintenance/ long oil change intervals more than anything else, and I have repeatedly put down 450+ wheel on pump gas on these bottom ends.