Our travel bags are made of the latest lightweight materials which are super durable and devoid of external straps so they don't get caught in baggage carousels.
Mesh bags or boat bags as they are often referred to as are excellent for boat diving where your kit lives on the deck which is often wet. These allow your kit to quickly drain whilst keeping it safely together.
Roller bags are handy when you have to transport a lot of dive kit. Wheels on one end take most of the weight whilst you pull the bag usually via a telescopic handle. Backpacks have been sewn into some bags where you need to transport gear over rough surfaces and wheels just won't cut it. Far more comfortable over longer distances than a holdall bag, just get your buddy to help you into the harness then you are ready to go.
Some of the very largest bags allow you not only to take all your dive gear but have enough room for your personal effects when aboard a live aboard.
Hybrid bags have been around for a while now but still have not really taken off in popularity yet, the Cressi Reg Bag changes between a regulator case for transport then into a mesh bag once on board.