Derivative Stats--yea or nay? (Patreon)

So derivative stats means the traditional STR, INT, DEX on a scale of 3-18 and then converting it to a bonus or penalty. 5E includes both numbers. Black Hack uses those 3-18 numbers in a roll-under system. Knave and Index Card RPG ditch them altogether and just use the bonuses. 

What is your preference and why?