At an NJ CCA gathering this morning, Prestige BMW had a few Dinan cars to test drive - An X650i, an E92 335i and an F10 550i (auto). The 550i is the newest addition I guess as they just featured it in Bimmer mag (October 2012 issue).
So step right up. First impression, mmmm, burble on startup (I think I need a Dinan exhaust on my car..). I like that, lets you know its a powerful car.
Pull away, hey look I can see the horizon, because the bow just pointed northward! Geez this thing is big car. Seriously big. At the first ramp I realized it was in comfort mode and fumbled for the suspension button which resulted in Sport+ in short order, to which the representative interjected with "you know traction is off now?.." Umm, yes, but since there were others in the car, I dialed it back one to sport. I did another 3 miles and was ready to hand it to the next driver. This car in its current setup is good to be driven in, drivers car? No.
As the article says, it needs suspension work.
Turbo lag? Yes, very much so. I don't know if its any better than stock, but I hope they got rid of more of it on the M5. I am sure you get used to it and learn how to spool up the turbos so it's ready to blast when you need it to, but you just feel so distant from the mechanical functions of this car. I tried holding gears with the needle at 4-5,000rpm, and still cracking the gas at those revs is rewarded with a gentle surge of slow mo before the wollop comes on. Then when it comes on, you're out of revs. It's boring.
Steering is accurate, but lifeless (I know, everyone has said that 100 times). This is a powerful, fast luxobarge for the corporate executive who likes cars, but needs something relaxing after another long day to coast home in. It's unique in an understanding way and I car guy needs that little bit of individuality. I get that, I really do, I think I may add a relaxing softly sprung auto box BMW to my garage at some point, just for daily commuting. But for fun? No.
I don't want to jump on the "BMW has lost its way bandwagon", but after driving this 5, a tuned version of a 550i sport package car, I have to admit, I am on the bandwagon.
Driving the E60 M5 is an event, I hope the F10 M5 proves to be.
So that wasn't a very positive review, but some machinery there was drool worthy.
EDIT: I know this car is not the specific car featured in Bimmer, but they only offer two tunes, 495HP and 515HP. So at a minimum it had the 495HP tune. As can be seen, it had the spring mod. Once the power came on it was forceful, more than you can do anything with in short squirts. I am sure it is stunningly quick in overtaking manouvers on the highway. The on/off nature of the power and hesitation of getting to on however, leaves me cold. The exhaust sounds nicest off idle. After that you don't hear much. It's a typically muted forced induction intake sound.