Don't know who you are speaking w/ but they don't know what they are talking about. All the M117's in 500's/560's are alloy. After 89 you have less of a worry w/ the head bolts pulling the alloy as they are phospate coated.
IMHO, the later the better.. I prefer a Euro spec car over US.. Biggest thing, service records and an owner that cares. Take your time, look at as many cars as you can. Check out mbcoupes . com for a buyers guide that does an excellent job detailing what to look out for.
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