There are plenty places to get stuff printed, and Moo is probably not the one to choose for cost-effective for printing in large scale.
That said, Moo is a really great option for creating high-quality printed materials in small batches for prototyping and testing parts of your business model.
Moo provides a killer feature that makes this possible. They call it “printfinity” which is, unarguably, ridiculous. That aside, what it means is, you can customize each printed item within an order (and on both sides). This, combined with short runs (meaning you can order pretty small batches of, say 25 or 50) makes Moo products very useful for high-quality prototypes.
Here are a few examples from Moo’s Inspiration Gallery…