well I don't agree from the 2 asus pg279q ips monitors I just had in the last week. the black level is not as good as my 3 and half year old samsung TN panel and as I said the glow or back light bleed in the corners can clearly be seen when playing games in slightly dark scenes.
I have no problem with the movement in fast pace games (and I am fussy with this) this monitor was quick enough for that but the glow is just not good enough.
the 1st monitor was shockingly bad and the 2nd was a lot better but still I could easily see it. (I didn't even have to look for it)
viewing angles on my old Samsung I agree not as good by a long way next to ips but I don't have any problem with my 27" Samsung from side to side in the view I look at it but up and down sometimes I do notice when I lie back more in my chair.
from what I'm reading the Dell S2716DG 27" 2560x1440 TN G-Sync 144Hz seems like it could be the best choice out there right now.
I think what we're seeing is just a VERY VERY bad example of IPS with this particular panel from AUO. It really is inferior in almost every way to what IPS should be, apart from the 144Hz aspect of course. The quality of some examples I've seen is really shocking, often just in uniformity alone... in 2016 it's really shameful, but I think AUO ignored everything that makes IPS so great and focused on pure speed, realising that the mere fact it was IPS would be a great marketing hook... but in reality it doesn't come close to the high standards of what IPS is capable of. Which is a crying shame really, because for many people it will be their first IPS monitor, having heard all these great things, but then they get this heap of junk! IPS deserves so much better, because it really IS!
You may be right though, the Dell is a very good TN monitor by most accounts... only people who've been used to quality IPS for years seem to have an issue, and for professional colour use I certainly don't think it's the right choice, but for gaming it probably is the best monitor out there right now, and at a good price. Unless you do somehow win the AUO lottery and get one of those gold dust panels!