Requires lots of self-discipline
I'd say for me that is the biggest challenge/con. It can get very hard at times to stay focused, there are so many things I need to do, so many things I want to do, and when you're not being monitored or pressured at all it can be way too easy to shove work to the back burner. I can't tell you how many times my "just taking a 10 minute break" turns into 30 or 60 minutes of being distracted doing something else. I've also learned to try to keep break-taking to a minimum for two reasons: 1, they almost always end up turning into a longer break than I intended, and 2, it's even harder for me to sit back down and get focused on work when I walk away from it for awhile.