I cruised back from Wales (140 odd miles) at 70 and then back and forth to work clocking about 280 miles in total. That was on £30 of fuel that I put in before leaving Wales at a cost of about £1.50 a litre (motorway services prices).
I used a MPG calculator and according to that it did just over 63 mpg.
I‘m more than happy with that!
And 70mph on the motorway/dual carriageway is a breeze. These cars are like a tardis inside. Feel so roomy in the front it’s unbelievabl. In the back not so much

but there’s enough room back there for the kids.