I agree as well that the 240 would be the most basic and perhaps reliable b/c of it's simpicity. But, I would look hard at the 300d with under 100k, or perhaps the most important to me would be the condition of the body, interior and paint. I have found as many others have that what people say on EBay to get a sale is often a far cry from the truth, so be careful. If at all possible, try to see the car in person and look for any hidden rust before you commit. Good luck, I'm jealous!
Adam B