Think opening par or bigger CM. There is buzz for OG Avenger flick, which I am not personally feeling but people are.
But legs should be worse, if its quality is par or slightly better CM. If quality is good, may be leg out par or better.
Will be like Civil War. Opening like Avengers film, post weekend bizz like a solo flick, even if it was better than Ultron (and TA). Opening like CM, post weekend bizz like a Ragnarok or Wasp.