Need a cordless impact wrench... Suggestions, please

I bought a DeWalt 18v 1/2" impact years ago. It has never failed to do anything I've asked of it. I was stupid though and got the single trigger model which thankfully DeWalt has apparently dropped with the 20v models. I chose DeWalt over other brands as I have a lot of other DeWalt tools. As has been pointed out batteries are expensive and the interchangeability between tools is a real benefit to me.