Should I accept a position with same pay, longer commute, but greater opportunity to learn?

In my current position, I enjoy the work, but there are several toxic co-workers. I have learned to put distance between them and myself, so they are reduced to a nuisance, not terribly stress inducing. The greatest benefit at my job is that I get every other Friday off and just work one hour more on all other days. That has worked great for me. Recently I was approached for a position within the same agency that has greater opportunity for learning, but it would be a lateral transfer with same pay, a longer commute and no Fridays off. My current role is highly specialized and not easily transferrable. My first thought before speaking with them was that I would only be interested if I could keep the flex schedule and get a raise. However, the position is one which would provide a great learning opportunity. My concern though is that I greatly value my Fridays off because my commute is long. In this other job, the commute is longer, but they said it could be arranged to work in the office close to my home one day per week. That would be the compromise. At first I was thinking I should take it, but after thinking it over, time is my most valuable asset right now, and these Fridays have been helpful in reducing stress. It would be hard on me to make the change, but I would get more experience. I am just not sure what to do right now. I am already mourning the loss of Fridays and I haven’t even accepted the position yet. The position is most definitely a career boost.