Hi!
I recently bought a Manfrotto Advance Travel Backpack and I am very pleased. This currently holds my A6000 with 18-105 attached. 30mm prime, 2 flashes and a reciever, kit lens, a set of filters, remote trigger, mini tripod, Manfrotto befree tripod (has an external pocket on the side which is a life saver!) macro extention tubes and a dedicated laptop compartment which comfertably holds my 15" mac. It also has a space for other things above the camera section which i can manage to fit a pair of jeans, underware and wash stuff in . Its a tight squeeze but it works!