Short Version: Not impressed.

Long Version: Was invited to a BMW event out here in so-cal, very basic type of function but essentially M vehicles as well as standard vehicles there for a test drive in the surrounding city streets (basically hand you the keys, tell you to follow the navi route, come back safe!).

Test drove the M5 on the streets and loved it. Definitely would consider it, good amount of power, nice growl, very spacious and comfortable. Very luxurious. Can't compare it to the C63 but if you are going the next step up, very very nice car.

Next, you get to take the M3 for a spin around an auto cross course with an instructor. Got to do about 4 laps after the instructor did about 3. Thoughts from the passenger side:
-Nice car.
-Seats are comfortable and nice, but they don't quite hold you in as well as ours.
-Carbon fiber looks good.

Thoughts from behind the wheel:
-Steering wheel. Not as nice as the FL ones we have. I love my C63 steering wheel from the way it looks, to the way it feels, and I get compliments about it and how awesome it looks from passengers all the time.
-Driving position is comfortable. Seats again are comfortable. Driver's seat seemed to grip me a bit more. (I feel the opposite from the few times I am in the passenger seat in my car, it feels tighter than the drivers side)
-Steering feel. Car felt planted, grip was good, pointed it in the right direction and it went there. Can't say its any better or worse than our cars.
-Throttle. Not happy with this at all. For anyone who says there isn't lag, I always felt like when I'd hit the gas there was a lag. Not to mention it still doesn't have the raw amount of torque we have so it feels like the power is taking forever to get there and I am already at the next corner on the breaks and the engine seems to have just started giving me something.
-Transmission: The one part of the car that I truly was impressed with is how fast and instant the shifts were. Blows ours out of the water.

All in all, I don't think it was a fantastic car. Great awesome car? sure it is. Would I even consider trading in my C63 for it. Not for a second. It does worry me about the W205 C63's engine.

Last word: I am so glad and grateful that I am able to afford and enjoy this beast of a car (the C63) on a daily basis. I truly think this engine and car is something that will be greatly missed in the future iterations of this model.

Thanks for your impressions

It's odd to me that German manufacturers are moving in the wrong direction with their performance lines, but Detroit is actually getting it right....ie Hellcat, Mustang, Covette, Chevy SS. Obsurd amounts of power, good performance, reasonable price and a great exhaust note.

If shlt doesn't change, I'm going American on my next go around. I don't dig force fed. Never did. It is one notch above NAWS on my performance gain gimmick totem pole.

Its a matter of time before the Americans "catch up". Turbos, electric turbos, hybrids, then full electric cars. The NA engine is a dying breed.

Has anyone been given a reasonable explanation why Mercedes refuses to put a proper dual clutch transmission in the C63? That and good cooling (for the track) would make this car nearly perfect.

Only if we buy them. Those of us in the performance community need to be as vocal as those in the enviromental community are about our needs and desires for cars. The European auto manufactures need to do a better job of weighing the opinions of those who actually purcahse their product vs. those who ride bicycles, occupy public spaces, and want everyone to drive solar-electric Lada's.

Mercedes should have a premium ECO division (like AMG is to performance) whose cars cost a 50-100% premium over standard models for those who want the technology, and actually wish to actually pay for it (rather than force others to via gov mandates.)

This is from a guy who proudly owns(ed) some of the greenest vechiles of their time.

Off topic-

Saph, your comment about M3 throttle response is exactly the reason why we traded our CTS-V. It never felt powerful until the blower spun up which, even though SC supposedly has no lag, seemed to take forever. Essentially useless for a daily driver unless you never let it get past 2 or 3rd gear so that it was always on boost. Of course when it was on boost it was tremendously responsive. But for real world driving, it soured me on FI.

Rediesel - sadly there are more of them then us. People that actually own performance (high hp) cars are a pretty small portion of the car buying public. So while our voices can still barely be heard, real performance will come with an ever increasing price tag.

It's funny you should mention lag because I didn't notice a massive improvement in throttle response moving from my 135i to my current C63. Maybe I should drive one now to see how that feels after getting used to my C63.

Totally agree on that. It's probably simply tu cut prices down.

Thanks for the impressions!

I agree with most of what you said except the lag part.

When in S+ and the transmission set to one of the more aggressive shifting programs, I found the throttle response to be outstanding for a turbocharged car. The torque is delivered virtually instantaneously and there's more of it available earlier in the revs as compared to the C63.

Does the throttle feel as linear as the C63's? No. But we're comparing a NA V8 motor to a twin-turbo I6 one.

I also found the M3/M4 standard brakes to be fantastic. Pedal feel was crisp, natural, linear, and progressive - plenty of bite.

Yes, I did forget braking impressions, but brakes were very good. Great bite and easy to figure out how much pressure you need to place to get the braking you want.

It may have been the nature of the autocross course, it was small and very tight, so it just felt from the time I floored it between corners that the power was just not coming on as fast as I am used to with our cars. With the C, foot goes down and instantly thrown back into the seat. With the M, it felt like i am coming out of the corner, wait a half sec, power comes on, instantly hit brakes as next corner is already there.

One thing I did forget to mention. That carbon fiber brace or whatever you want to call it in the engine bay is absolutely amazing! Loved seeing that in there.

PS. I may be a bit more sensitive to the lag just because I have never really driven any turbo charged performance vehicles. So all my comparisons are to NA cars and especially to the C because its my daily.