As for the gap – well 10% isn’t insignificant, but we also don’t have as much data for the Omega as the Focus. The Omega could have been used on more economical routes for all we know. And Poddy’s average was higher until he changed his driving pattern recently, as he told us. It was up about 43 or so last time this came up IIRC which is 10% difference.
I think 35 is pretty good for the Omega, but I think 40 or even 43 isn’t great for the Focus. But again, Poddy is into this stuff so I would assume that the journey profiles aren’t great. Then again, his best tankful is only 45.
To wave the flag for newer cars, my auto Passat is faster than that old Omega, has many more safety features and gets 60mpg on a good run. So ner 🙂