They are great reliable cars and will not decrease in value at all. I think it would be a good investment no matter what. My dad has always wanted one too. Make sure to find a good one in nice shape. Also they made the 250sl too. Same body style but a 2.5 litre six. I know this is a M3 post and I'm a proud M3 owner. But I'm thinking about buying my dad a nice car for his 60th. He always wanted a 1967-1971 Mercedes 230 or 280 SL...you know, those cool little 2-seaters. And if he doesn't like it and wants a Miata or something, I wouldn't mind having one of these for the weekends. It seems like there are very knowledgeable people on this board. Anybody know anything about the 230 or 280 SLs? I would appreciate any help.