Hi and I use my Zed daily and cover around 350 miles a week. My journey to work is a mix of country lanes, town traffic and motorway and I'm averaging around 24 mpg. I also own an old hack that I use during the summer months for towing, but the cost of keeping it taxed, insured, etc, for the full year would be greater imo than the savings on fuel if I used it daily.
The Zed is a brilliant drive and for the performance it is not an expensive car to run.