Simple difference question

[mixfloors]

Hi guys, I am considering a 29inch monitor for my second computer, I play minimal games on it and do office work and a fair bit of PS graphics work on it.
I see LG has two versions available (as choises are a little limited in Aus)
http://www.pccasegear.com/index.php?mai ... s_id=23516
and
http://www.pccasegear.com/index.php?mai ... s_id=23280

There is a $50 difference between the two, (which is of no concern, save, that I like the more expensive versions stand, visually) but what I cant figure out is the difference between the two, save that one is and AH-IPS panel, and the other is an IPS.

Is this the only difference, and what is the significance of it ?
I am also considering an Asus 2560x1440 27" monitor as a third option, but would prefer the wider screen as a first choise.
http://www.pccasegear.com/index.php?mai ... s_id=21516

Regardless of which monitor I choose, it will be hooked to an i7 940 with a GTX 780, so there will be no GFX power capability issues.
Any opinions or suggestions are most welcome.
Thanks in advance
Mike