Need your opinions on Copics vs Promarkers?

Ok my friends, I want to invest in some good quality markers for stamp coloring and crafting. I have seen both Copics and Promarkers used on various sites but am not sure which to purchase. Please leave a comment about your preference and why you prefer to use this brand. Also if you know of any links to sites that you have found that might be helpful that would be awesome! I really would appreciate any input you have! Thanks all!