Rear leaf spring Question 74 Dart

Hi guys,

Replacing my rear leaf springs with new ones from General Spring. I saw that there is an option to add and extra leaf if i wanted. I have read that others have added the extra leaf to improve handling but came with a stiffer ride. I am unsure as to the pros cons of doing so. The car is stock 6cyl and just looking to use it as a summer driver until I get into the restoration. So I don't want a ride like a truck but I also don't want that sway. Any help is much appreciated