I have tried out Moo.com for my next review. Now I know what you're going to tell me... "This vendor is a professional card printer so of course the quality of the postcards is going to be better!" And I'd have to agree with you. And if I agreed with you we'd both be correct. These cards came out amazing.
Overall a great experience. There are a few things to note. They let you choose almost as many designs as you want to print. Super cool. With most print vendors you need to print a certain amount of the same design and if you don't they cost an arm and a leg. Not so with Moo. One downfall was you can't choose a matte picture side. And they have a few templates for the back side but very limited. So no customization on the writing side.
Overall minor complaints.
I will definitely use them in the future for small customizable jobs.