Dick McGuire is our best transfer but he gets an asterisk for war time eduction at Dartmouth. Kenny Mac, a dear friend for years, did transfer from NC and he produced one of our most unlikely and treasured championships in '65; he could shoot foul shots with Mullin any day when the game was on the line. Brust was a NC transfer and, without a doubt, our most courageous and tough player ever. He had no skin on him by mid season and was one of the biggest fan favorites ever. Kevin Loughery was from BC and really changed the way we played; he was an almost unheard of, for the time, 6'4" guard (sometimes forward) from Cardinal Hayes in the Bronx and a very long term coach in the pros afterward. Ron Rowan has to be mentioned from ND because of "the shot" in '86 for the championship against Syracuse in the BE.
As far as transfers out, Rashon McCloud was the best and won championships for his team. I don't recall any others coming back to bite us or anyone who made an important winning difference where they went .
As an aside re: Holy Cross, Bob Cousey would have been right up there in transfers to StJ had Coach Lapchick not strongly advised him to stay with Doggie Julian, Coach's friend. Cousy , from St.Albans , Queens lost interest in the Cross after his freshman year and sought out Mr. Lapchick. Coach took the high road, as did Coach Lou after regarding prospective transfers, and, in this case Cousy stayed at home. He did pretty well in his pro career as well as with the Cross.