I purchased a base model Space Grey about 2 and a half weeks ago. After about three days, the machine started to "creak" every time I picked it up with one hand. It sounded like it was breaking. I took it back to my local Apple Store and they switched it out, no problem. Yesterday, the down arrow became jammed, sticky and noisy. I took it back to the Apple Store. Apple agreed there was a problem. Unfortunately, they had zero models in stock, so I am waiting for a replacement. Not a huge deal, but I've had two MacBooks with two problems. What are those odds??