No idea what size a sterling europa 555 is, but I tow a Hymer (MTPLM 1600kg) with a 55 plate diesel (136 hp DCI) and it is fantastic.
Cruises at 60 mph, accelerates well even uphill, and very stable over the 5000+ miles I have used it. It has a 100kg towbar limit with a short overhang from the rear wheels which helps a lot. Fuel consumption is about 37mpg solo running about generally, and towing on motorway gives 26mpg. These figures are corrected for the wildly (10%) overreading speedo which I have accurately calibrated over 100miles of motorway with reference to the marker posts, some maths required as these are in km!
Additionally you get a great view driving with a large sunroof as well, and a proper full size spare wheel.
Yes there are turbo problems with this model, mine has had to be replaced but Nisssan paid, most should be done by now.