Probably not - but if you can get get a reputable free one why not? Will maybe have some effect on your battery drain.
Of more concern are the permissions that different apps demand. I recently had an update for one app which seemed to be primarily to allow the app to access my contact list - I promptly deleted the app. This was one of the Open Office apps from the Google Store - why it could possibly need my contact list details is something to speculate about!!!