Good device with slight weaknesses

Unfortunately, I have not yet figured out how the drill bit can be stuck on the adapter when the center drill is mounted - that does not work in my opinion.

In addition, the drill bits sitting partially not quite accurate and jiggle something. In a hole in the wall is not so important, angry at a hole on the drill, because somewhat inaccurate. This "game" is produced by apparently not exactly shaped receptacles on the drill bits - some wiggle slightly in the adapter, while others sit at attention without play in the adapter.