I had looked for years to find a treadmill I was happy with, even tried out a few elliptical as well.  But all the ones, from inexpensive to expensive to even club quality, they were either poorly made, bulky, heavy, or belts often slipped.  With an elliptical they always, always hurt my knee.  So with a prior back injury and a blown knee, this was a daunting task.  After trying many units in several retailers and specialty stores and even purchasing several, yes several units which all ended up gathering dust and always ended up selling them on craigslist for no where near what we paid for...