I sure as hell would; since Aston really knows how to excel at the F1 implementation. I have yet to drive a DB9, but I have driven a Vanquish with the Stage 4 F1 tranny, which as I understand is exactly what they based the DB9 tranny on. The quality and speed of the shifts were absolutely mindboggling; and when downshifting the transmission handles the rev-matching on its own, so you never, EVER got that surge when the new gear engaged. Rather, it felt like a good, clean, perfect shift followed by immense acceleration. The smaller details of operating such a car as a daily driver take some time to learn; the sales director who provided me the Vanquish drive mentioned that it's advisable to keep the car in neutral when stopped for a long light for instance, and that there was an additional trick required for reverse. Neutral was acheived by pulling on both paddle shifters simultaneously.
I was also told that the Vanquish (and perhaps the DB9 too?) has several driving modes for use with the paddle shifters... one is the sport mode in which driving the car is an active effort (most fun!) but one could also choose the full automatic in which the car would behave like your standard, traditional automatic passenger car. Only faster. So yes... I would definitely buy an automatic Aston.