Hi, I'm Richard...
Hi, I'm Richard; I'm a bag addict.
I have sixbags and always seem to need one more.
I am going to China in April and purchased a great Lowepro Pro Roller Mini Portable Rolling Hard Case which is well within the carry-on size restrictions on China Airlines.
However, I found to my great dismay that China Airlines has a severe weight restriction for Economy Class carry-on luggage and the Lowepro Rolling Case empty is within one or two pounds of the maximum weight. That certainly wouldn't give much leeway to carry gear.
Fortunately, I still have a Lowepro Mini Trekker backpacker which only weighs a couple of pounds empty and will fit my gear just fine. It doesn't have rollers but my main suitcase is a roller model and I can just fit the Mini Trekker on top for any long treks around the airport or from the transport into the hotel.
By-the-way; although I have many bags, I don't usually shoot carrying a bag. The bags are simply to store and/or transport my gear. I usually carry two cameras/lenses on an OPTECH Dual Harness and the rest of my gear (which occasionally includes one or two extra lenses), in my photo vest.