I've had two euro diesels (currently just have the one--190D). There is basically zero problem with parts. Once in a while, you'll have to bug the parts guy a bit to make sure he understands it's a Euro, but MB will supply the parts.

I've also never had any hassle with insurance. I don't think the insurance company ever even brought it up.

Both my euros came into the US normally (military, I think) and were "updated" the way they had to be. My current 190D had to have the speedo replaced for some weird reason--don't know the details except that the previous owner gave me a lot of correspondence relative to it. But that was his problem--not mine.

If you've got a euro, feel blessed. They're generally better (simpler) cars than what was imported as a US Mercedes!!!!!