I've had my R350 for 6 years and about 80,000 miles. I am the third owner and had my indy do a PPI before I commited to purchase. They were familiar with it as the PO had had it serviced with them. The only issues I've had are front shocks, rear air bags and a power steering reservoir leak. One electrical gremlin is my side marker light coming and going.
It's got a ton of room inside, it'll swallow two eight foot kayaks with the seats down. I'm actually thinking of moving to a newer one, 2011 or '12. They aren't that popular so prices are pretty good. I'm not sure about the diesels but the gas engine gets a solid 19 mpg (US gallon) average.

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