I have the base radio too. I have installed 5x7 in the doors and rear deck. It sound a little better. As far as what type/brand, its your call. I'm keeping the head unit, due to so so review of the kit made by Mitra. Hopefully in a few months other radio kit options will be available. My next step to to add an amplifer. I did noticed the sub enclosures are attched to the door panels. I was thinking of installing 6.5 compoment speakers, by cutting into the panel. That will wait after the amp install.