All New Marvel Collected Editions

[The Lucky One]

Is the Busiek Conan omnibus pretty much the same as Dark Horse's Colossal Conan omni?

Or is there less material collected in the upcoming Marvel one?

As RudyZeBoulet correctly pointed out, it contains only the issues written by Kurt Busiek. The Colossal Conan collects issues 0-50, including issues by Busiek, Truman, and Mignola. (On the other hand, the Colossal does NOT collect the Book of Thoth mini.)

Also, the omni will be standard omni size, whereas the Colossal volumes are larger dimensions.