Another option is expansive bits. With a small one and a large one you can bore from 1/2" to 3" and everything in between. I have over 500 expansive bits in my collection and can say for sure they aren't all the same.
One thing to look for is cutting balance. There are two cutters involved. The movable cutter and the fixed cutter. There may or may not be two spurs. The best balanced cutters are when the fixed and movable cutters are somewhat opposite each other. To make it easier to make, some bits have the fixed cutter closer to the movable cutter. This puts all the cutting to one side of the bit and makes for a less balance rotation of the brace. The ones with a side adjustment screw are easier to adjust precisely but there are other things to look at. The Russell Jennings design, called a solid head, Do not have any scales and there are design changes that happened after Stanley bought them. The earlier ones before Stanley are better made. The Steers patent ones as well as the Wright Convalco ones are good. If buying make sure to get ones with both cutters for the full range. Additional cutters were available up to 6" but you need a lot of leverage to remove that much wood.