I'm in the process of developing the business side of my photography doing portraits and such. I want to post available sizes and corresponding prices of prints on the website that I'm designing but dont want to until I figure out the best place to do my printing. And i want to do everything right from the beginning.
My question is, do most professionals who produce portrait prints for clients use services such as Snapfish or MPix? And do these sites produce prints that are excellent enough to do my images justice? (assume that my images are absolutely perfect).

If not, what do you suggest?
And no, buying my own professional quality printer is not an option.
Thanks!