These tools are of a very high quality, considering they are intended for use on instruments (ie, won't encounter much abuse) I will probably have these for the rest of my life.
I have quite a few guitars and am yet to find any screws, nuts, bolts or anything that doesn't have a corresponding tool in this kit.
The bag the tools come in is about the right size to fit into a guitar case.
The only gripe I have is that the handle piece of the multi tool is a little bit bulky and it can be tricky getting into a Strat's truss rod hole or a Gibson's intonation screws beneath the strings. With that being said, I haven't encountered any issues that keep me from making any adjustments, just a few awkward movements.
Oh yeah, the string winder seems a bit cheap but honestly I would have paid the same price for this kit without the winder so I'll consider it a bonus.
All in all I fully recommend these tools if you need a handy set of guitar tools. I've found myself much more interested in keeping my guitars intonation, action and neck in check because I have every tool I need at my disposal.