Product review (5 stars): Good Drill/Driver but could have improved functionality
A bit about myself: "do it yourselfer" w experience with 14.4 volt Makita drill/impact driver NiMh Kit.

I've started using the smaller Li-ion tools including this product, the Hitachi 10.8V impact driver as well as Makita 10.8V drill/impact driver combo for comparison.

The 10.8V tools are slower and have less power than their 14.4V counterparts. Having said that they obviously have the better form factor and still deliver very good power to weight/ergonomic ratio.

Hitachi has excellent ergonomics. Its a pleasure to use this drill/driver as the grip just fits nicely in my hand. The tool is well balanced. The power is more than adequate to drive in 2 or 3 inch deck screws.  I see more and more drills coming out w more power to drive screws.  Problem is that w more power the more likely you are to twist off the head and break the screw.

The thing that could be improved w this tool and a functionality that could be added in the future is a 2 stage drill/driver switch.  400 rev/min is good for fast/precise driving of screws but is not good for most drilling.  I would like to have the same drill be able to handle both functions.  The Makita 10.8V drill/driver does exactly this but lacks the excellent ergonomics that this tool has.

I still rate this product 5 stars but with the clause above.