Old thread but in case anyone searches and finds it, I'll add my impressions.
Freemont - Friendlist place, and best location for a test drive. Jesse is a good person to seek out.
Mountain View - Least friendly (of the three listed here), and worst location for a test drive, unless you are very familiar with the area and are mostly interested in driving in snarly congested traffic.
Stevens Creek (san jose) - Middle friendly, middling place to test drive. Less strange and complicated than MV, but nothing like the open roads available in Freemont.
(I mention the surrounding roads because for me, on a test drive, if I have to figure out what the heck is going on with traffic and intersections etc in an unfamiliar place, with a salesperson yabbering directions at me, I'll have a tough time paying close attention to the car, and driving it the way I like to drive.)
PS: In terms or pricing, all were within a few percent of one another, essentially meeting the best truecar (or consumer reports) negotiated price, with little haggling, which was under $500 over invoice on what I was shopping for, though all were steadfast on the Maco fee -- meaning that while they said they were under $500 over invoice they were REALLY a couple hundred over $500 over invoice. YMMV depending on what options you are buying, what time of the month you show up, what incentives are in place, yada yada.