What influence did the Gardiner family have on Darcy's opinion of the Bennet family by the end of the novel?

When Darcy runs into Elizabeth in the garden, she is surprised by his civility, and especially by his kind inquiries about her family. These inquiries are particularly noteworthy considering the harsh criticism which he made of her family during his proposal and in his letter. Further, when Darcy meets Elizabeth and the Gardiners later in their walk, Elizabeth is surprisingly pleased at how kind he is to Mr. and Mrs. Gardiner, especially considering that these are precisely some of the relations which he had previously thought to be a reason for shame. In spite of the fact that they are a much lower class than he, he enters into conversation with them and even tells Mr. Gardiner that he is welcome to come to Pemberley and fish as long as he is in the area. The Gardiners are down to earth people and Elizabeth respects their sense apperception. In turn, the Gardiners speak highly of Darcy to Elizabeth.