I play games with 1440p 144hz 27" Acer xb270hu. Current graphics card is fast enough for it in most titles, prior to that had a 1080ti. 1080p on it looked good so it really depends on the monitor and how it scales. But even with 1080ti, 1440p still performed well, it's not a huge stretch over 1080p, not like 4k.
What i mainly come here to say is my experience with 27" 1440p has been great, had the monitor for many years now and size wise is much better than 24". Also there's no real need for extra image sharpening, as in anti aliasing, have never used it in any game since having the monitor, don't notice the need and some more fps has a result.