Ask HN: Does a supervisor/university matter for a Masters in CS

So I am in a bit of a peculiar situation and thought I might ask. A few years back, I made a career change to get into CS and ended up doing a diploma. While on the diploma I got a full-time job as a coder. Now, I don't want to quit my job and I'd like to do a Master's degree (towards ML\NLP). I have a supervisor but he is not very well known in the field. Neither is the university. However he is willing to accept me as a part-time student for a thesis project. Is this a good approach or should I consider other options (such as doing course-based masters) ?