I know what you mean by the salesman looking at you weird. That is a serious knock on the M4. Being able to plug your USB into your 12V is a definite plus so I can see the Passat edging out the M4 there too. Lastly, a point you missed, is that the Passat is probably quicker to the 10 foot mark so the M4 isn't the crackerjack race car it's being made out to be either.
Good informative review.
Much better than all the drivel being posted in the forum with all that objective data nonsense.