I've been using Metropolitan Town Car for 3 years. I won't use anyone else. They are reliable, polite, prompt...everything you want in a car service.
Vladimir, the owner, is a former Russian Air Force pilot who moved to the US a bunch of years ago. He runs the operation with near military precision. The cars are clean, the drivers all wear suits and are unfailingly polite. They arrive on time (actually 10 mins early for pickup in most cases). If they don't know precisely where to find you or are otherwise running behind they call. They are also pretty flexible - this fall the return flight for our family vacation was delayed to the point of requiring an overnight stay in Vancouver. I kept calling Vladimir with updates and was told each time, "Don't worry, we'll be there." And they were.
As the name implies they drive town cars not stretch limos, which is fine by me personally. For reliable, quality service I highly recommend them.