The proform gr 80 by life fitness is an outstanding amazing machine. We bought this machine when I had recevied a shot for nerv damage in my toe and had to take six weeks off from my daily run. The life fitness proform gr 80 was purchased at a resonable amount and came with a fantastic one year warranty!  It is the best machine i would say overall for your knees, joints, and also your feet! I get on my proform gr 80 daily and can say I don't feel like I've lost any endurance or speed. If anything I do feel like I am working more muscles than when i do run. The different levels and settings on...