The air cushions use the same technology and materials used on ultralight inflatable sleeping pads. They are designed to withstand your full body weight sleeping on top of it against the ground over night.
Using it on a backpack against your back is nothing compared to that. So rest assured the air cushions and the pack are made to last.
If you accidentally punctured it, it's very easy to fix also. Just find the leak, wipe the surrounding clean, and paste the repair patch (included) over the leak. Anyone can do it.