Although I would not consider myself a world traveler, I have done some extensive traveling in my short nineteen years of living. This includes flights to places like Guatemala, Mexico, Israel and the Caribbean (not to mention tons of intercontinental travel).
When I travel abroad, it is usually for at least two weeks. This requires at least one very large suitcase and an average sized duffel bag. Because international travel requires more security restrictions and much more extensive searches of your belongings, they are treated much more like cargo than anything else.
It is my opinion that because of the careless treatment of luggage by airline staff and security, as well as the way in which luggage is carried on airplanes, that buying expensive luggage of any sort is a complete waste of money.
Not to mention how easily luggage is lost and never seen again. Not only will you be missing all of your belongings inside the bag, the bag itself will be gone forever.
So instead of buying bags because of a brand names, buy bags because you know you will need a new one soon, especially if you travel a lot.
And think of what you could do with the money you would be saving by buying cheaper luggage. You could use it for something that will actually be worthwhile and potentially have a longer lasting life than a bag that most likely will get lost, ruined or damaged in a few uses.