I was writing a meta post on another site where saying "Done." was a sufficient post. In order to meet the character limit, I typed the sentence:
Sometimes five characters is really enough.
After looking at it, I changed it to:
Sometimes five characters are really enough.
Somehow, as a native speaker, the first one still feels better to me, although I can't figure out why that is or if my feeling is misleading me.
Is my initial pass on the sentence grammatically correct? Does it mean something different than the second take?