What kind of cordless drill-driver do you use?
I have an 18v DeWalt XRP Drill/Driver/Hammer Drill.
I have been very happy with it. The only down side is that it is a little heavy, but it does everything I have asked of it.
I have only had Craftsman cordless drills up to this point, so I guess I'm just not use to the weight of a "real tool".