Naturally the faster ram is faster and your 7th gen CPU and 2xx serries board will natively run 2400 without having to overclock it.
Now with that said you will likely not notice any difference from gaming.
Considering price is damn near the same you might as well get the faster ram, but if you say already had 2133 or found a spectacular deal on some, I wouldnt loose a wink of a sleep over it.