Advice on Camera Bags.
Roller cases will not damage your gear inside. The Think Tank are good as are the Tamrac ones. Choose based on the interior and compartments and keep in mind the international luggage max size of 22" x 14" x 9" which includes the handle.
I have used a Tamrac Strongbox for overseas and USA travel for 14 years and it is still in very good shape. I have changed the interior layout a dozen or more times and so it is in active use regardless of how much my kit changes.
A rolling bag will count as your luggage while a medium backpack does not on the airlines. The trick is to make a backpack look small and this is where the Gearguru Bataflae type of pack is good.