24" would be 122PPI (pixels per inch) vs 108PPI @ 27" so it would be sharper, but everything on screen would be smaller (text, windows interface etc).
High PPI is great while in game, lower PPI is better for general desktop. Most people prefer around the ~100PPI mark. I have a 27" 2k and it's just right for me. I'd suggest finding a store with displays and checking out the difference.