What's the difference between Runaways Deluxe HC I and Runaways Complete Collection I? I want to pucharse one and don't know which one to choose.

I’m not sure offhand, to be honest. They’re both collections of the same material, one in hardcover, the other in softcover. It’s possible that the HC is longer and contains more issues than the softcover, but it’s also possible that it doesn’t. I don’t have the books handy to check on this, sorry.