Prius highway rating of 4.4 L/100 km (53 mpg-US / 64 mpg-imp) Volvo V50 highway rating: 3.8 L/100km - this is the 'extra economical' diesel, with start/stop, aero body and aero wheels, so a good match for the Prius - seems odd that all that extra tech wouldn't give them much improvement? I guess city driving it may be better but I don't have time to dig out the figures now.