may seem unnecessary to spend on a set of hex wrenches, screw drivers, pliers, and a ruler; but i'm happy i did. i'll probably get rid of the packets of EB cleaner (nice touch, but i dont use stuff like that normally) and keep a spare battery in there. room for a set of strings would've been nice, but i guess you can just put them inside and zip it up.
i adjusted 3 different truss rods last night after opening it, and the wrenches accommodated the 3 different instruments. i didn't adjust any bridges / use the smaller hex wrenches, but im confident the sizes are there.
this may not be enough to open your own guitar workshop, there will certainly be some instruments with odd truss rod sizes that you'll need a specialized tool for. i'm a full time musician - music educator, and i think this is perfect to keep in my gigbag for teaching, i do setups on students guitars and basses pretty regularly, and having everything in a neat little case is going to be convenient.