Always good to have a spare car alongside an ///M, I drive mine everyday and it does get a bit tiring handing out wads of money for everything from tax to insurance to fuel to watching the CBS indicator in iDrive warning of impending wallet opening (like brake discs/pads, etc.).

They are great though when you yo want to drop the hammer! Any you'd never tire of a proper exhaust note. Another alternative is to just drive it for 6 months of the year and garage it for the winter.

A word of warning, I would not put too much of a stretch on your wallet for a car. It's just not worth it. You want to be able to enjoy the car without worrying about the next big bill.