I have had my Nordic Track A2550 for two months now, and I love it already. I bought it so I could run, and it feels like a very sturdy machine. It is also softer than most other treadmills I have used, so it is easier on the knees. The treadmill also allows the user to adjust how soft or firm it is, to possibly lower the impact on a person's knees even more. It has a 2.5 hp motor, which allows the treadmill to run flawlessly. Most treadmills I have used only have arrow keys to adjust the speed and incline. What I love about the Nordic Track is that it has buttons that run up the display that allow...