The Maxpedition Gearslinger line up is designed with a single shoulder strap that crosses over the chest, similar to a messenger bag. The strap goes from the top right hand corner of the pack and connects to the bottom left. This configuration allows the pack to sit comfortably on your back however it can be pulled to the front of your chest to access the contents in a hurry. All of the Maxpedition Gearslinger have a dedicated concealed carry pocket that is easily accessible when the bag is pulled to your chest. So, if you need to get to your firearm it is a quick motion instead of having to dig through a backpack for it.
The Maxpedition Kodiak, in my opinion is the best of the large packs offered in the Gearslinger series. Most large packs that you come across have a big main compartment with very little organizational structure. You basically cram as much gear into them as you can, and then have to dig through all of the contents to find what you are looking for. The Kodiak is extremely organized internally, everything that you put into it has its place so there is no digging for your gear.
I am really impressed with the majority of the Gearslinger line up but for a big pack I would go for the Kodiak over the Monsoon. The Maxpedition Monsoon is a larger overall bag however it does not nearly compete with the attention to detail and internal organization of the Kodiak. For me the Kodiak is also a better use of space. Although the tear drop shape of the monsoon is really cool looking, it is not as practical as the Kodiak's use of space.
For More information on all of the Gearslingers by Maxpedition check out my full review site at Maxpedition Gearslinger Reviews