I picked up a car on 11/23/2008 from 614 Cobb Parkway South in Marietta, GA, which was a Maxima that we requested. So, now during the walk through of the car everything on the outside appeared to be in good condition. While sitting in the car I tried letting down the driver's window and it got stuck a quarter of the way. Went back to tell Sarah about the window problems so I wouldn't be held accountable for it and she told me she could put me into an Altima. I stated to her I didn't want an Altima I had asked for a Maxima. So, Sarah's customer service was great, because she said that she would try to get another Maxima for us before Tuesday upon departure of our Thanksgiving Holiday to Texas. Once leaving Sarah, I had some errands to run and got on the express way and now the car is shaking, vibrating when brake is applied, and car is pulling to the left below 60mph and above 60mph it is going to the right on top of the vibration that could possible give me a headache on an thirteen hour trip. So now, I went to the airport to try to save the company some time in rectifying the problem instead of getting upset and once again giving the company another chance to make me a satisfied customer without all the extra run around and rudeness. Of course I received rude customer service by a guy named Matthew Baker who stated, "There is nothing physically wrong with the car so he could only offer me a pick-up truck or a PT Cruiser in place of the Nissan Maxima," which I am paying a premium rate for. So Mr. Baker listened to my previous issues that I have had with Enterprise and I asked him could he please switch out the Maxima for another Maxima. Well Mr. Baker didn't hold his composure very well at all like I was annoying him and told me, "I am sorry that you didn't like my suggestion and there is no way he could switch out the car." It was two in the parking lot and there were several being returned at the time I arrived. This is SO UNFAIR and I understand that life isn't fair but I have remain calm and kept my composure with everyone including road side service and rental agents.