Why didn't you tell them the truth?
rep there @ 5th ave
is a joke. Told them about lines and they said never heard of or not an issue now, due new displays are in
rep telling me I can upgrade SSD to a larger one through website, they swore by it until i showed them it can't.I stayed there cause I had time to kill and also a lot of eye candy during the summerIf you didn't find the line on your MBA on the first 5 min, let it go...
Just to add my observations..
My New MBA v.C is a 9C90 and has no visible lines.

My latest MBA replacement (my fourth machine) doesn't have the lines. It's the 9C8F model. Let's pray I don't have any other issues that cause me to have to roll the dice.
As I have reported already, my 2.13 MBA has no visible lines.
I have not had time to put my new MBA through it's paces since I have been so busy this week, but I have noticed that when browsing and scrolling, dark elements on the page seem to flicker as the page scrolls, until it stops scrolling. Otherwise, the screen is crystal clear. Is this a MacBook Air screen issue? Is it present on all MBA screens, only affected screens, or is this common on laptop screens in general? It has been so long since I have used a laptop, it's difficult for me to remember.