I know the IMS discussion has been done to death but this was the best thread I have read:
Who has done an IMS change (New Oil Fed Design Idea) - Pelican Parts Technical BBS
Had my 2003 Boxster 2 years and (touch wood) had no issues with anything. I may get the IMS done when the clutch needs replacing but it certainly doesn't bother me driving it.
What is of more concern is the endless threads about the IMS, any potential new owners will be scared off as soon as they do some research on these forums. Still, far worse unsaleable cars out there to be stuck with.