At only 11 lbs difference between the CF roof and the metal roof (without sunroof) I think the overall difference with the sunroof may be 50lbs. I will probably track the car only 2 or 3 times a year. And the difference in performance will be small. I can enjoy the sunroof 365 days a year. I think I have to go with the sunroof.
However I was at my dealer Thursday night and the CF roof does look cool on the M6.
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