The larger the screen the worse a TN screen gets in the edges due to the poor viewing angle.
Also, looking into response times only doesn't necessarily tell the truth. It highly depends on the measuring method. Black to black tells longer but more accurate response times. Grey to grey is much shorter so it's usually used for gaming oriented monitors to fool the customers. Unfortunately the method is rarely told unless you find a review where they have actually measured it and compared it to the manufacturer digits. I just found a review from 2011 about my HP LP3065 30" S-IPS monitor. It told that the grey to grey response is 6 ms and off-on-off a whopping 12 ms. However, I've never experienced any ghosting effects in the games I play, AH maybe being the most fast paced.
I suppose the poster on another forum is right in claiming that the manufacturers use far from scientific and real life compatible methodology varying from model to model and choose the best looking values for marketing purposes. A trustworthy review and your very own eyes are the only reliable ways to tell if a monitor is good or not for your purposes.