Just from a brief lookup, Vital Farms seems pretty legit plus they have the Certified Humane label. But I like that their website lets you look at the particular farm on a live video feed! For example, link to where these eggs came from, Farmer Johnson’s farm🐓 I just loved to see the little ladies clucking around😊
In my experience they're not as terrible as some of the otheres... definitely not where production farming chickens are concerned.
They require a minimum of 60 acres per operation with the land sectioned off and the flock rotated between parcels. Parcels and production have to meet certain, fairly rigorous, quality control standards or Vital can pull the contract and no longer will purchase eggs. Contracts renew every 5 years, and if it's not to the QC standards and proper maintenance/upgrades aren't maintained, the contract will be pulled.
This is all personal experience from looking into contracting with them and raising eggs. I didn't wind up going through with it due to startup costs and certain logistics... but I did speak with them quite a bit before I waived the whole thing off.