25" for 2560x1440 is quite demanding in terms of pitch depth, if it is just used for general computing like web site browsing and video watching, I think it is fine. However:
I myself was considering between 25" and 27" a few months ago, UP2516D vs UP2716D. Did a side by side comparison in a Dell shop, and decided that 27" is the bare minimum for this resolution, so I ended up buying the 27". They only had Windows on the demo computers so perhaps Mac OS could handle UI scaling a bit more decently, but after a few months of usage of the 27" there are time I find text being fuzzy or UI elements in professional apps being too small, and I keep the monitor at most only 2 feet away. I can't imagine dealing with the 25" in this regard, and I guess for coding usage your case will be even more demanding.