Having a 10-in-One and using it are different things. I not much of a fan of those either. Any hard cranking with the nut driver sleeve -that serves to hold the phillips and other bits in place when its used as a screwdriver- will eventually burst the thin steel its made of. Never had that happen with a purpose-built nut driver. The heads of single purpose nut drivers are a lot heavier and can take more abuse, as well as having much longer necks so you don't grind the handle (or your hand) on a mudring or some sharp part of a panel which is much deeper than the shaft of a 10-in-one. Strenght and space constraints are my main criticism of the 10-in-one. On the other hand, for A/C disconnects its one stop shopping, provided none of the fasteners are rusted/live/buried deep in the cabinet or case.
