I would say one down side is that things feel like they are moving very slowly sometimes. Because the project I work on is so huge, it will take a long time (a few years) to complete it. I am really impatient and I want to see the results of my work right now!!
In certain jobs you “clock in” and “clock out” – this doesn’t work so well for me. Partly because I like what I do, I tend to think of ideas etc when I’m out and about or even on holidays. It would be nice to switch off now and again