I just upgraded recently to a 28" 1440p monitor and I notice two things. First, MiRai is right on about those larger resolutions suffering from "tech issues" for things like font scaling/size and performance in the multiboxing context. 1440p is just about as high as I'd want to go for anything under 32" and even then it might be sub-optimal. Down to preference really. Though with the advent of 4k stuff, the lower-rez displays are seeing a very nice (for us consumers) price drop since everyone else wants the shiny.
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