I used the ProForm 415 Crosswalk Treadmill for several weeks and found that it provides a decent cardio session, but sprinting at full speed for me wasn't an option. The highest speed level is 10, which isn't a tremendous pace, but once I adjusted the incline level I was able to counter the lack of speed to have an intense workout. I found the adjustable handles to come in handy when warming up for upper body exercises. The handles provided excellent blood flow to my muscles, which allowed me to eliminate a couple of warm up sets without sacrificing safety. I was also impressed with the shock absorption of the deck. I can jog or run for a hour without feeling any type of discomfort in my knees. The only issue I have with this treadmill is that the hand sensor readings are all over the place. The sensors said that I had a heart rate of 155 BPMs and I hadn't even started running. I would definitely recommend the ProForm 415 Crosswalk Treadmill to anyone looking for a quality low cost treadmill that folds up.