I just had 7 out of 10 hatch about three weeks ago but I think the hatch rate has more to do with the eggs than with the hen. I got my eggs from someone about 5 miles away. They had all been laid within 24 hours prior. They weren't shipped. They weren't xrayed. I let them sit on the counter a few hours before putting them under my gal.
The year prior I put 11 eggs under the same hen. Only 1 hatched. However, they had been flown across country and had been xrayed.
IMO, if you can get fertile eggs locally, you'll have a better hatch rate.