I tried growing Atlas tomatoes many years ago. They showed promise but the garden was destroyed by a mid August hail storm.
My doctor had one last year and raved about it. These are not the same thing as they were selling as Atlas years ago.
At least 5" diameter
At least 4 ½" diameter
eBay
If you try to get them delivered after frost date, you will most likely get duds.
In the wild, the egg cases survive all winter fine. I get mine early and stick them around places outside and let them hatch naturally.