A few questions regarding entry into the US with an immigrant visa for the first time. Does it matter if I purchase a round trip ticket (I'm finding it to be much cheaper) even if I may not end up using the return portion? Also, how much time should I allow at the port of entry? My port of entry would be at my stopover since there aren't any direct flights. Would 2 hrs suffice? My port of entry would be most like be Chicago O'hare. Thank you.