Thought I'd circle back and show the impacts that I bought because of this thread. I'm going to try them out. I also have a 3/4" Makita corded impact wrench not shown here.
The 1/2" has a very nice feature, a wheel adjustment for speed/ torque so you don't overdrive the tool.
The 3/8" wrench has a 5.0 Ah battery, but the 1/2" has a 4. Go figure that one. Both batteries charge in about 20 mins. Impact sockets are by Snap-On and Wright Tool.