Wow... I use a DeWalt 14.4V drill for my "light duty" screw and drilling work.
I break out the Milwaukee 18V for heavier stuff (7/8" step bit, up to 4" hole saws, up to 3/4" augers, hammer drilling up to 5/8"...) Anything more than that and it's the 120VAC Northern rotary hammer or the 120VAC Makita angle drill depending on the task at hand.
I wish "they" made all drills/drivers with an adjustable clutch. I'd rather use a clutched drill with holesaws than an angle drill, especially a non-variable-speed one...
My partner's Milwaukee angle drill has VSR, but no clutch. Still a great improvement, though.
I'll stop rambling now.