http://www.bhphotovideo.com/c/product/301645-REG/Lowepro_3448010_Rover_Plus_AW_Camera.html

It could obviously hold everything I need for the A1 and mountain hiking. At only 5.5 pounds it seems good. My problem is it is I believe it is

Linear inches: 50.5"

Which is 4.5" over the standard carry on size. Do you think if its not full i could just squish it down and no one would notice? I would like to use it to bring my camera over to Taiwan, then hike in the mountains with it.

No protection..I have a petrol backpack also Kata is good..a lot of cushion..and helps hide the camera from thieves.

with the space available i think i could add cushioning. I haven`t found a kata or petrol good for hiking, where i don`t have to lay the bag flat on the ground to get the camera out. Do you have pics of your setup? Also I don`t see how having petrol brand name stamped on a bag would turn thieves away, if anything they know you have expensive equipment because of the brand.