I have found the Ingersoll Rand Model IR2131P to be very nice impact gun for the weekend user. We use them here at work to open stuff up out on the decks of
oil tankers. Everything on a ship deck is rusted and corroded on. These guns have a nice feature that they have more power when you are taking something off than when your are putting it on. But you can find them on the net and at some of the local home improvement stores.