I can see why you're looking for an alternative with such a big jump in your monthly payments. But you are also right in that hybrids tend to work less well for high-mileage drivers, being best suited to running on electric for short distances around towns and cities, using the engine and braking to charge the battery as necessary. According to our Real MPG database, a diesel Cee'd typically returns around 70 per cent of the official combined cycle fuel consumption figure, with 74 per cent for the Niro. But you should probably bear in mind that drivers who have entered data on the Niro have chosen it because the hybrid technology is well suited to their driving needs. Hybrids have improved in the latest generation of models to perform better in the real world, so you should probably look at the latest Toyota Prius (also check the Our Cars section of our website as we've been running one of these for a few months), and possibly the Hyundai Ioniq Hybrid. The Ioniq uses the same engine and hybrid system as the Niro, but if you don't need the SUV body style, it might save you a little in fuel through its improved aerodynamics - which become a bigger factor at higher speeds, such as on dual carriageways. The SEAT Leon diesel is a very good car and should perform well as a 25,000-miles-a-year company vehicle, but I would also look at the latest Vauxhall Astra and Peugeot 308, which should perform equally well, to check if they would save you any more money than the Leon each month.