Ok, bro just replied that he went to Wabash Diamond company and was very happy with their service. He is exceedingly shy and not particularly good on the research (I know, I know...I tried) but he ended up being treated very well and purchased a beauty for his now fiance.
They have a website you may want to check out.
My DH got my ring at Fuenfer Jewelers in Wilmette. I had to get the ring resized and ultimately have a bridge put in b/c my fingers are really wonky; however, they were just incredible to work with. Apparently they spend hours and hours with my husband showing him lots of diamonds. Lucky guy.
I have sent my mom there to get her ring re-pronged. She loved them.