Hatcheries, for the most part, produce very healthy chicks. No complaints. Their stock is also highly productive, in that their birds lay lots and lots of eggs, as the hatcheries make more profit if their birds are selected for productivity. I've lots of hatchery birds and like them alot. They are cheap to buy and readily available most of the year.
That said, once you have heritage, pure bred birds, they are something to behold and enjoy. They grow very, very slowly, feather in slowly, but can awesome instincts to forage. The personality difference and behavior difference is noticeable. The heritage, pure bred bird isn't just about showing either. They tend to go broody, where that trait is almost bred out completely in hatchery stock. Such birds can only be secured from specialized breeders and preservation minded keepers of the old line birds. Once you narrow down what you want, by way of a breed, you ask around here on BYC. Many preservation breeders of old line, heritage birds hatch very limited numbers of them, so it is best to plan far in advance and get on a list.