240Hz does have benefits compared with 144Hz in both frame rate potential and perceived motion clarity. If you can achieve consistently high frame rates to make the most of it, it's def worth it for competitive, top end gaming in my opinion. You have to live with 1080p right now if you want it, and limitations of TN Film technology in general but for gaming it's a very good option. There's quite a few 24.5" models around and a few less 27" too. Asus have a 23.8" model coming soon too.
Ps if you also enjoy motion blur reduction backlights, the LG 27GK750F has an excellent one that even runs at 240Hz and does a great job of eliminating strobe cross talking ghosting as well!