There is no correct answer, as everyone has a different way of life. The fuel card will come in really handy if you do a lot of private mileage, particularly right now, but only you can determine that. For me, i opted out of a company car and now take a car allowance. I reclaim mileage from the company (and HMRC), Again - its just a calculation based on personal circumstance. If it is a company car, i wouldnt worry too much about the battery performance drop off, as you will be handing it back in 3 years to get a new one.