Hex shank is a great asset. With the drill extension, you can quickly change bits without having to reach into the drill chuck, unscrew, insert or squeeze the drill chuck with each bit change. So pre-drilling the holes and then inserting the screws will speed up the project. They are not intended for metals other than softer ones such as copper, aluminum etc. They are mostly good for wood, plastic, etc. They have a nice appearance. Two piece clear plastic case so you always know you have them at a glance. One could argue that the divider body, with each size marked with the word "speed" on it, is a chore to find the right size bit, but if you look at the same thing you get a good and quick approximation . Nice set at a good price.