How many miles could someone expect to get from the engine / tranny before a rebuild / new engine is in order? How much would either of those cost? I want a 300e with the 5 speed very much, I'm just concerned about the high mileage. [I know the diesels can go 300,000+ no problem if taken care of properly, I don't have any experience with the gas engined mbz's though.]

Thanks,
James