I have a Heritage T/A van of the same weight/design as yours. I towed this van for the first two years I had it with a Landrover Freelander 2.0 TD4. On paper a similar issue to the weight ratio with the Merc. (but well within the car manufacturers tolerances). This outfit was as solid as a rock, towed across France twice and into Switzerland & Italy. Never once felt that car/van match gave any cause for concern. Power & stability excellent. I now tow this van with a new Shogun LWB, which is obviously much heavier, but consider that the outfit was just as stable with the Freelander. Very interestingly while in France last September, an identical Fleetwood Heritage pulled onto a tiny rural site just after me, which was a coincidence in itself - however you might be particularly interested to note that the car pulling this van very happily was a nice shiny Merc E Class (diesel saloon). This outfit was on its way to Spain for some late sunshine. Happy driver/happy car/stable van by all accounts...! The Heritage is in my view a well balanced, stable van with a Winterhoff stabilising hitch as standard kit too. I think it will be fine with your Merc - providing you are sensible (as in all things!). Go for it, happy towing. Richard.