That's a drag on insurance. Seems a little high though--I pay around $75/mo for the 55, which has the larger V8 with about 350HP.
As far as the car's longevity, it's all about how you treat them. The drive-train on these is rock solid--the M113 is a fantastic motor and should last 150k+ without issue. The interior bits is where things get a little dicey. My parents have an E430 (different chassis, but same drive-train and very similar interior) with ~180,000 miles on it. Still drives like a champ, but the interior started to go at about 150k.
So insurance is about 300/year more than your alternatives? To me, that difference is worth it for a much more unique car. But honestly, the maintenance is going to be a lot higher for the MB than the VW. The fact that the MB will be 10 years old soon means that there will almost undoubtedly be at least a couple of things that need to be addressed as soon as you take possession of the car. In my case, this turned out to be some minor noise in the suspension and the rattle of a failing window regulator in the driver's side door. For now these issues don't bother me enough to have them fixed, but expect similar minor issues with any car this old.
I also considered a Jaguar XK8, although it has the same disadvantages along with much less practicality. Still, it's simply the most spectacular looking car this side of 50 grand. My advice? Just say screw it and convince yourself that no other car will do. Just look at it. This one is $11,000 with 59k miles. Again, supposedly pretty reliable with an economical, gutsy V8. It's a no brainer, right?

All depends on how much of a premium you put on a rare car with a beautiful design--for me it was quite a bit.
Edited by Andrewc2232 - 12/8/11 at 11:40am