Impacts are good for driving fasteners into wood, concrete... they drive it right in (you could probably put it right through a 2x4) with little effort. They do not work for drilling holes, when i meets resistance it starts the impacting action and causes the bit to spin slower or not at all.
Drills are much more multi purpose, dill, drive and more.
Good drills do not end with DeWalt, try Milwaukee, Makita, and if you've got the $$ Hilti makes the best tools