I buy this product a month okay , and have be use it pretty consistently since . the bottom line be , I like it , and I do not regret my purchase . I do not think that it be a miracle product , though . as for the pro , it be safe , affordable , and convenient to use . also , the dvd that come with it offer good instruction . at first you may feel a bit of a burn , but after some time , most of the excercise do feel more natural . as for the con , I do not think that it live up to the hype . sure , it may offer some tonage and some improvement of muscle strength , but it really do not feel like a well-rounded workout . this have become my commercial break gadget -- it be a great thing to squeeze in throughout the day . real definition and health benefit , though , take more dedication than the `` six minute a day '' that the product claim be all you need . when I feel like a real workout , I 'll do something else . another con be that the weight can feel really awkward for some of the one-handed excercise . not awkward as in a `` I be not strong enough to do this '' but more a `` this feel weird and unbalanced in my hand . '' as part of a overall fitness plan , I think it serve its purpose . I do not think that this product alone will deliver perfect arm , though .