Here's an interesting exchange of letters from 1858. They were printed in Hamaggid. The first is a dispatch from Minsk, signed by "D.", about the formation of a "Beis Mussar" in Kovno under R. Yisrael Salanter's influence. The writer is not impressed, doesn't think R. Yisrael's "Elixir of Life" addresses the educational needs of the time, and is quite sarcastic. He particularly deplores the involvement of R. Yehoshua Heller, one of R. Yisrael's notable students, and an opponent of Haskalah, whom he had the displeasure of hearing in Minsk, where he slammed Hamaggid from the Maggid's pulpit.
The second letter, sent from Padua, is signed by one Yosef Isser Eindorn (sic? Andorn? Einhorn) , a physician, who says he was a student of R. Yisrael for three years. The doctor is quite upset that Hamaggid printed the other letter, which he considers slander of R. Yisrael. He says that he doesn't want to get into the ideological battles in Russia. His point is evidently that what appears as a straightforward letter is really another salvo in a battle that the readers who are not there will not understand. He says that the matter of his emissaries in Minsk is a lie. Also, R. Yisrael is not an enemy of Haskalah. In fact, it was he who encouraged Eindorn to become a physician. Furthermore, if the study of mussar is opposed to chochma, then you must indict all the earlier authors of Jewish mussar literature, Rabbi Shlomo ibn Gabirol, R. Bachya, R. Moshe Chaim Luzzatto. He writes that in fact in Padua there is a Beis Mussar which studies the mussar classics every day, attached to the Ashkenazic synagogue in that city. Who heads this havurah? Shadal - Samuel David Luzzatto - and who will say that they (i.e., the Italians) are against chochma? He closes by admonishing the editor to please live up to the motto on the cover, האמת והשלום אהבו, "Love truth and peace" (Zech. 8.19).
The editor basically thanks him for his letter. He sort of accepts it, but points out that if it's true that R. Yisrael is not responsible for errant students, then neither is Mendelssohn.
Doubtlessly many have heard about another incident involving R. Israel Salanter and Hamaggid a few years later (1865). R. Yisrael's son Lipmann was basically raised without his father's constant involvement, and not surprisingly evinced interest in other things. He graduated from a gymnasium, became a proficient mathematician and attended university. Hamaggid printed a small profile about him, and added some praises of his father for supporting him in his education. Several issues later R. Yisrael sent a letter saying that although it pains him to say it publicly, since his name is being used to promote something he doesn't agree with, he states that he is not proud of him. On the contrary, he is greatly troubled by his son.
I guess you could call a college boy an "אברך" in those days. Here's a picture of Lipmann who, sadly, died when he was only 29 years old.