Rollamaster

Hello folks. I am not an expert at selecting speakers but am willing to upgrade my (headunit - JVCKD-G300) speakers from stock to either Pioneer TSA690R or Infinity 9603i. (my friend is selling both these pairs) I think infinity is a better choice but has a lower sensitivity. I donot have a AMP - what is my best option here for good sound quality. I drive a corolla and am willing to have good quality music within with a decent volume. Please help. Thank You