If you’re concerned with your particular order, please feel free to email Woot Member Services and they can answer any questions you might have about your purchase.
Having been (and still am) a longtime competitive runner, I can say upgrading to the highest treadmill you can reasonable afford will pay off in the long run, no pun intended. The rewards for spending $400 more up front will save you frustration from inferior material, maintenance, and provides reliable, higher quality workouts.