Although, I recently read a "how to win a tshirt comp - 10 tips" article on a blog (I cant find it for the life of me for some reason! Im sure i bookmarked it!) and one of the top tips was using a small colour pallete to keep printing costs down.
I recon it could look sick in a limited colour palette to maybe 3 anyway but thats just mean (if your asking, black, white, green and blue)
I'll be honest, I clicked on here thinking it would be a piss poor design where the designer just wanted some 'easy' votes by advertising, which I'm not sure I agree with. But it turns out, I love the design and would pay for one of those Tees