I've gotten chicks from Ideal, Privett, and Townline.
BY FAR!!! the easiest and most efficient operation was Townline. Their staff is pleasant and knowledgeable on the phone. And I got exactly what I ordered (plus extras!), healthy, all alive, packaging material was above average compared to the others, and paperwork/billing was excellent. All of the chicks have grown up to be extremely healthy and productive egglayers, every single one of them.
With Privett I always receive some cockerals in the sexed pullets, always, every time!, no matter the breed. This year I ordered 6 RIW sexed pullets. I received 5 pullets and one cock. Of the 5 pullets, 2 have yet to lay an egg and they are over 7 months old now. However, their roosters are pretty nice for the breeds. A neighbor won a ribbon at the state fair with a Privett cock. And in general I just have not had great success with Ideal birds as egglayers once they are grown. The ordering, sexing, shipping seems fine (though there always seems to be a a few fatalities in shipping but I've come to expect that)...their birds just don't grow up to be as productive or friendly. The feed stores who order from Ideal always seem to have quite a few sickly looking chicks in every bin when the orders come in.