I am a incoming first year grad student this fall. I have contacted prof A during when I was applying and talked to him during the visit. He strongly encouraged me to join his group.
After the visit, I emailed students in Prof A's group and other current grad students. I started feeling that his group atmosphere is not the best for me, and I don't want to join him anymore.
He is really nice and recently offered me an educational opportunity that is only shared by current students. I am grateful and I really want to take that course.
I feel guilty right now b/c he is so nice to me. But I don't want to spend my next 5 years in a group I don't like.
Is there any way that I can let the prof know I am not interested in his group anymore? Do I have to give up the course he offered? I am not assigned to prof A so I have the freedom to choose.