I know not everyones and audio head like me, bu if i was you and had room to spare in boot, under seat etc, and if you had any extra cash, then Id think about a new h/u to run them off. possibly even a new h/u (nothing too pricey just nice) and a cheap amp.
Its just that you cant get a good sound out of uprated speakers until you amp them tbh, and the output of the original renault h/u is so minimal I doubt youll notice much diff. wih new ones