I had a cordless 1/2 impact for a couple years at home. Found that I didn't use it enough and the batteries went bad. Replacement batteries were damn near the cost of the gun. Purchased a corded electric impact.... problem solved.

I have a 3/8 cordless impact at work and I use it daily (Zenex). Batteries have lasted 3+ years, but I'm swapping them on the charger probably every other day.

....IF you go cordless, be mindfull of where you are charging your batteries. Member Rhinodart lost his garage over a cordless battery charger and that's not the first time I'd heard of this happening.