1) Get the newest one you can afford.
2) The 2000 should have less bugs in it than the 1997.
3) The I6 was prone to leaking - the V6 is an excellent engine.
4) Upkeep will be the same.
5) The 2000 will get better mpg.

I've talked to two mechanics here in Houston who are Mercedes-only and have been in business for over 25 years each. When I asked this same question to them, both of them (without hesitation) said "get the V6". Also, the V6 will have the 5-speed transmission - another plus.

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- Brian


1989 500SEL Euro
1966 250SE Cabriolet
1958 BMW Isetta 600