If you get a good lead from a REAL LIVE source, not an internet testimonial, of a fair to midland line of birds, from Hatchery A, in a breed you want, that's one thing. Bee's use of the word "grab bag" is descriptive. You just flat won't know, most of the time. Pig a poke for sure.
If you want bred to standard birds, wish to show, want the real McCoy heritage birds you've seen displayed on other threads, you're simply gonna have to get to know some of the reputable folks who have them, breed them and will include you into the supply chain. There aren't enough of such birds to supply everyone in the world with them and not everyone even needs such birds, frankly.
Back to hatchery stock. If you do get solid intelligence on Hatchery A's XXXX strain of birds, what we'e done is this. Order a box of 25 or 50. At 5 month to a year? Pick through. In that batch will be some winners. I'm telling ya. Some good, solid birds. Not show, not SOP particularly, but good birds. Dump the rest. Eat them, sell them, give them away, etc. I am the only one foolish enough, I reckon, to make this recommendation, as I sure as heck don't hear others saying it around the forum, but it is as reasonable and plain old straight forward as picking 5 good 2x4's out of a stack of twisted ones at Home Depot. That's all I got to say about that.
But, if you say to me, I only want 3 birds as pets, well, then that's a whole 'nother deal that someone else might be better advising you on.