But remember hens go broody on their schedule not yours. Not all hens are reliably broody for the required length of time. You can only fit so many eggs under a hen.
Both are good. If you want a few chicks---when you get a broody hen---set her. If you want a lot of chicks, set the incubator. With both you need to do your home-work to have better hatch rates. My broody hens(over 70 sets last year) hatch 98 to 100%. My Incubators---hatched over 6000 last year and had a 95 to 100% hatch rate. I like Both---no Cons with either.