Fished this weekend with a friend who has a ten inch auger. I have a five inch hand auger. We both complained about each other’s holes! Although a large hole can have advantages, like getting the fish’s head started up the hole, the smallest hole you can get away with will save you MANY more fish. Most ice fishermen that I’ve watched make the mistake of trying to hoist the fish out of the water and onto the ice. The loss of buoyancy provided by the water puts a whole lot more strain on your hook, line and the fish’s mouth, resulting in an increased chance of the hook dislodging at the surface. If this happens in a large hole, the fish will eventually get turned downward and get away. However, in a smaller hole he’s stuck, allowing you to grab it or, like I like to do, get my ice scoop under it. I my opinion, use the smallest hole you can get away with. It will increase your productivity. Plus, it takes less time and effort, and a smaller auger is more portable.