well as much as I like an manual trans its really not practical to have one in stop and go traffic. I was under the impression a auto trans is faster because the gears are always engaged. when you shift a manual trans there is that millisecond of disengagement of the drive train. then to spend another $15-20,000 for the upgrade then void your warranty, does not sound like a really good ideal. but if that is what you want, I am sure it would be nice but if your going to spend $60,000.00 for a car I would get something else that is already a matched system, instead of trying to make something else work. just my thoughts, kevin