Porsche Marin, formerly known as Sonnen Porsche, is truly the best place to get your Porsche. The whole buying experience is critical to me -- I don't want to feel bad parting with my money, and one little misstep is all it takes to ruin the whole experience. After a few experiences with Porsche Marin, I can confidently say that I will not trust anyone else with my dreams.
Now, having said all of this, it's worth noting that Brett Payne is my Porsche guy. Period. He is a die hard enthusiast, just like me, and is not a sales guy -- he operates more like an agent, in that he facilitates my transaction, he never "sells" me anything (I walk in already sold on what I want). His sense on building cars is impeccable, as well. He's often steered me away from bad (options) choices, or towards good options to add -- I know a lot about a lot, but it's hard to truly know everything. Brett makes it all easy for me.
In terms of guys I've worked with or interacted with, there are many other top notch guys on the Sonnen team: Emil Rustamov (Finance Director), Bill Lamphere (General Manager), and Mr. Peter Sonnen himself. All are class acts.
I'm heavily biased in that I've had many positive experiences at Porsche Marin. Hopefully yours are equally positive, but obviously like anything else in life, your mileage may vary. Drop Brett a note (his email is on their staff page on their website) and have him help you with your dream -- just don't be an annoying client, please! Otherwise, I'll regret recommending him. ;)