If angle of view is important, IPS monitors claim to be better off axis -- and they are better than TN.
Thing is, the fine print:
As one goes off axis, the contrast ratio begins to lower.
Viewed head on, a high contrast cPVA screen delivers a genuine 3000:1 static contrast. Other screens, including IPS, deliver 300:1 to 1000:1 (which is not outstanding). The vastly overpriced Samsung triple 23" monitor setups made for Eyefinity use the super high contrast cPVA (or they did). I have three 23" Samsung cPVA monitors in the house (bought at about $200 each -- vs $1800 list for the 3 Eyefinity monitors). No 27" version.
When they say 178 degrees field of view, the criterion ALLOWS a 10:1 contrast ratio from that off axis position (very very very faded view). So, the true, usable off-axis view will be less than the advertised number -- because most folks will think 10:1 is unusable.
As you indicate, for something like Eyefinity, setting the side monitors at an angle solves much of the problem. It is actually practical to set them so as you turn your head to look at them, they are "head on" -- so no fading (mine are set that way).
Regarding the best 27 inch. The only one I own is a Samsung 27" combo monitor/HDTV. Its OK, but being TN, off axis viewing fades quickly. So, I have nothing that I would recommend from my own experience.
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