It is reported from Abu Huraria (r) that the Messenger of Allah , peace and blessings be upon him, said, “Among the women of Arabia, the best of them are those who descend from the Quraysh;  for they are very affectionate to young children and preserve the wealth of their husbands” (Bukhari vol.ii, p760) 
A'isha (r) narrated from the Prophet (s) that Jibriel (AS) said, "I have searched throughout the Earth from east to west, and yet I did not find a man better than Muhammad (s), and have never seen any father's sons better than the sons of Hashim." 

In Sahih Muslim, Wathila ibn al Aska' narrated that Muhammad (s) said, "Allah chose Kinana from the sons of Isma'il, and Quraysh from Kinana, and from Quraysh the sons of Hashim, and finally chose me from the sons of Hashim." 

Al Abbas (r) said Prophet Muhammad (pbuh) said, "Allah created the creation, and put me in the best groups, and the best of the two groups; then He chose the tribes, and put me in the best of their families. Therefore, I have the best personality, the best soul and nature, and possess the best origin among them."