I gave up on the v2 omnibus a long time ago, when they've announced these Epics, although we got some double dipping since then (although I think mostly it's the epics getting released shortly after an omnibus and not the other way around).
I don't think the Michelinie IM omnibus sold well enough since it was on clearance for a while and also there is no new Iron man movie on the horizon either.
But I think you won't regret buying the Epics, the stories are great!