I've had all them all at one point... various generations of M3, 997.1 Turbo and 997.1 C4S
My favorite is the current 997.1 C4S - best blend of power, performance and daily living.
Honestly in my opinion, you really can't compare a standard M3 to a 911 because the 911 is purposely built as a sports car whereas the M3 is a hybrid - it starts the chassis creation for the global masses, then tweaked and updated to appeal to sports car enthusiast.
Ok... if I was to compare stock for stock, my C4S will run circles around any of my M3's in overall performance (not just 0-60)
I took both cars to the race track and the dominance of the C4S shows up fairly quickly - it's able to handle the onslaught of the track much better.
The 997.1 Turbo was insanely fast with sportschrono and will run circles around both.
I drove the new 991S for 20-30 miles, amazing car. It takes daily super car expectations, to new levels.
The latest PDK is utterly butter smooth and extracts most out of the engine at any speed.
The attention to detail is the best of any car I've owned.
If money is no object, I would get a properly equipped 991 version, over many other sports car.
In a couple of years probably trade in my 997's, and move to a new 991 C4S but its probably going to be $130K+
If I was in the market for a 2011+ 997 in any flavor and with a budget of $100K+, I would be patient and get either a used 991 or 991S!
And for those who haven't driven a 997 and 991 back to back...they are both good drives, the 991 is more refined and allows you to extract more performance at the limits. With that said, I will probably never be able to extract the full potential of my 997's - it's that good.
Last edited by mark_12345; 03-25-2012 at 10:46 AM.