It's the 1.6 HDi that needs avoiding; the oil feed to the turbo tends to fail, causing the turbo to self-destruct. The 1.4 HDi, for some reason, doesn't suffer the same issue. As LGF said, PSA-derived and used by Ford, not Renault afaik.
An older 'premium' German car has the ability to drop a ferocious bill or two. At least the likes of the mid range french stuff will be cheaper on parts and cheaper to fix....