I don't understand why you would still end up using your car 4/5 days. Are you not allowed to use the company car to go to your gf's and after work stuff?
What is your current payment on your car? How much is it worth if you sold it? Can you sell your current car, cancel the insurance and save the payments over this time? Keep in mind that cars are the single largest item we buy that 99.9% of the time will go DOWN in value. Can you put that money in to something that will go UP in value during that time?
That's how I'd look at it. I would sell my depreciating daily driver and find a car that held its value, for fun, while beating the company car to hell.
Not sure why you'd take the car when you could use the extra money to pay for gas, your car insurance and any accidents you might get into.
What's the obsession with taking the car? He already has one. All he's saving is gas. And he's in Europe. He doesn't need to drive to travel.
His insurance would certainly be lower if he didn't drive his current car, and his maintenance would be reduced by the lack of miles being put on it. Isn't gas generally more expensive in Europe (I'm sure it varies between country/region)? At US gas prices right now, $220 goes a long way. When gas was $3+, there were plenty of people spending that in gas alone each month. I think it would come down to how much you are going to drive a car. Take the car if you want to drive a lot. Take the cash if you don't want to drive everywhere.