I have two Nils hand augers (4/2" and 6") That I power with my DeWalt hand drill. The system is great and super light!
But! For anyone thinking of spending big bucks for a Nils Power auger I have to friend at Lake Champlain that have found that the Nils cutting edge is the best for hand drilling , they tend to dull faster with the speed and power of a gas power head. So, it would seem to me that the choice of a gas, or propane powered auger will provide a wide choice of brands. If I were to buy a new power auger I would choose the one that I could sharpen at home or have the quickest turn around for sharpening service. I think the Nils would be a great investment attached to a battery operated power source. In any event , if you are looking at a hand auger I can't fault either of my Nils after 4 years of use.
They are easier and faster than any drill that I have had the opportunity to use!
Dick