I've made room in my monthly budget, just waiting to pull the trigger
Suggestion:
It all depends on your own perception. The 6 series is an excellent vehicle (in terms of luxurity and sheer driving pleasure) and the equal of the mercedes in the luxurity/power aspect. The BMW's handling however, is A LOT better than the Mercedes' so in the end I would not consider the mercedes in this equation as someone else suggested. The Porsche 911 is hardly a competitor as it is smaller, lighter and more a performance car than a daily driver.
Someone pointed out that you pay a lot of interest on a lease of a 6 series, I think that number is way too high, but yes you will pay interest when leasing. If you think it's worth it, go for it. If not, then don't.
