quick-wittedness vs mental quickness

quick-wittedness and mental quickness both are nouns.

Word	Noun	Adjective	Verb	Adverb
quick-wittedness	Yes	No	No	No
mental quickness	Yes	No	No	No

As nouns, quick-wittedness and mental quickness are synonyms defined as:

quick-wittedness and mental quickness: intelligence as revealed by an ability to give correct responses without delay

Other synonyms of quick-wittedness include quickness.

quick-wittedness (noun)	mental quickness (noun)
intelligence as revealed by an ability to give correct responses without delay	intelligence as revealed by an ability to give correct responses without delay