new interior speakers

I own a 1990 Buick century with an JVC Arsenal KD AR 600 headunit and I was wondering what kind of speakers should I go with, Total Customs recommended me to cadence 6X9's in the rear and cadence 4X6's in the front, I was wondering if anyone has heard anything about cadence speakers like sound quality or reliability. My current speakers are some CHEAP ASS duals same measurements which the duals didn't sound bad at all the sounded clear and decently loud but they have ALL blown at almost the same time (may have something to do with all the abuse they got in the BLuick) and I need something to replace them with.

Just buy a pair of good components and put them in kicks/doors up front.