It's tough enough balancing a full-time job and a personal/family life. When you add an educational degree on top of that, then it gets to be very tricky! There are many people who find that they are more productive when they're pushed to the limit. Of course, you can get burned out very quickly if you're being pushed to the extreme, so you have to know your limits.
For me, I enjoy reading and learning new things. In some ways, I wish I could be a lifelong student (as long as someone pays me so that I can pay the bills, take care of my loans, etc.). However, the reality is that we need to be productive with our time, resources, and talents. I enjoyed getting my MPH (master's in public health) while I was working full-time. It was motivating and stimulating. I admit that there were days when I just wanted to be finished with my MPH. Once I was done, I felt a huge sense of relief. However, I also know that I can do it again - and that's why I've been thinking about business school. I'm still not sure where (and if) it fits into my life and my career plan, but I hope that it will at some point.
If you've been considering a part-time education and you're currently working full-time, keep this in mind: many schools offer you the option to enroll in one or two classes as a non-degree student. This gives you the flexibility to test the waters and try things out first. If you find that the work/life/school balance is too difficult, then you may need to reconsider your options. However, I'd have to think that many people would find the balance manageable - as long as you prioritize wisely. If you have the luxury to stop your day job and enroll in a full-time educational program, then you're very lucky. That's probably the best learning option if you can afford such an investment. As for me, I need to play the balancing act of work/life/education in order to stay alive and support my family. That's the practical side of life.