for the little amount of large screwing like you mention that I do, my standard drill/driver works fine. If I did it a lot, I would probably get one. What I do not like about them...
obnoxious loud noise
lack of fine control
breaks more screws
they are hell on bits and bit holders
Pros for them, that I see...
Fast, powerful, can break stuck screws loose, annoys the wife, easier on the wrist for prolong use.
Yeah they're kinda brutish. I usually pre-drill first (with my regular Makita non-impact drill), so I can run fasteners through with the impact driver without splitting wood. I am kinda OCD. I don't like splitting wood even if it's just the top part of the board on a rough carpentry project like stair steps, deck, etc.. And even if my only payment is supper and beer.
Once I pre-drill, the impact zooms the fasteners in easily.