The C990 Pro is one of the best sub $1k treadmills ever made. With that said, a serious trainer will need to step up to the $1,499 range.
A fantastically designed treadmill that can easily fool you into thinking that you can come across a $2,500 treadmill. When you remove the motor cover, the motor looks like one from a $2,500 machine but when you run on it, you will notice that the lower quality electronics has a hesitation that the high end machines simply don't have. When you realize the heart rate grips don't work you might not care becuase you got such a deal on the rest of the machine.