This works very well for me.  Its great when traveling to maintain fitness since it weighs about a pound, and I use it as part of a weight and aerobic workout at home as well.  It is a nice change of pace and allows you to do some expercises not easily done on equipment.  As another reviewier rightly observed, its not a substitute for heavy weights to failure.  Its a high rep toning device that will mininimize backsliding when you cannot work out otherwise and add to a full workout with a little something different.  For the price it certainly earns its keep.