I purchased the first of these bags at a  Samsonite outlet store.  I travel overseas, and I was very hesitant that this bag could make it with 50 lbs inside it.  I purchased it because the lady at the counter told me that the Samsonite warranty was for 3 years and they would cover it (unless it was accidental damage like it got punctured with a sharp object, etc).  So, I decided to try it.  And to my surprise, these bags can carry a ton (and not all has to be soft items like clothing) and are very durable.
On 1/16/12 - I have taken my bags twice to Panama and twice to Mexico full with all 50 lbs that I am allowed, and they are still in good shape!  Great, great bags (if you have enough to fill them with)