The cordless right angle drill is something of a niche product. It's designed for a specific application: getting into tight spaces. But this category is not concerned with getting into a tight spot to turn the occasional screw. If that's what you need you should look for a compact cordless screw driver. This category is for when you need a significant amount of power in a tight spot or when you need to drive in tight spots all day.
If you need to get in tight spots all day or need significant power in tight spots, then the cordless right angle drill you need is the
DEWALT DW960K-2 Heavy-Duty 3/8-Inch 18-Volt Ni-Cad Cordless Right Angle Drill
We have to be honest here. The right angle drill may be the red-headed step-child of the cordless drill industry. It doesn't get as much focus as the 18v cordless drill or the hammer drill. There aren't as many choices. But we do think this drill will get the job done for you. It's a heavy duty drill, but keep in mind that's in the context of right angle drills. It's heavy duty in a small drill pond. But it does have the juice to keep you drilling/driving for a long time. And it's a quality drill. It should hold up to a lot of wear and tear.