Diesel would be very nice for towing, where torque is what really counts, not horsepower at 5000 rpm!
Just back from two weeks in the UK with a rental car. Ford Mondeo with a 2.0 turbo diesel engine. Very nice in this size car! Over 200 lb-ft of torque coupled to a 5- or 6-speed transmission so she had plenty of Go. Computer showed an average of 48 miles per gallon for about 1500 miles of mixed driving. Was paying £1.18 for low sulfur diesel -- per Liter! -- so the high mileage was appreciated. Diesel was cheaper than "petrol" in Britain by about 10p/liter.