Drove the car. The SMG is similar to the DCT, but there's a legit 1-2 second delay when shifting via paddle. Even in auto mode, you feel that jerk when it automatically switches gears. It's not bad and does feel more of a manual due to the delay in gear shifting.
The DCT on my M3 is smooth, but I did not find the delay in the SMG on the M6 of annoyance or of any lesser while driving.
The main put off for me was many multiple owners, and I can tell the car was sitting outside. M emblems were a bit faded, and the interior pillar trims were coming off (tell-tale sign for me to know the car has definitely sat outside, and not garaged)
For some reason, I preferred the E63 M6 interior over the E9X M3. Fewer buttons are always nicer.
Would I have gotten it? Definitely, if it was 1-owner, and lesser than 50K miles. It's worrisome especially when you see +3 owners for an E6X M5/M6.
I do have another 10 months to look for an E63 Black/Black... White/Black (or red) combo.
That Interlagos Blue and Red combo.. can never ever find that one!