It can be a rewarding career if you work for the right people. I do recommend this career because it is growing and pay rates are getting better. The pros are working on interesting projects and meet interesting people. THe cons are long hours, lots of late evening emergency service calls. You should get as much training as possible before you go into this field.
Plumbing is a forgotten career in an age of computers, offices, and meetings. Yet almost everyone has or uses plumbing. The ease of office-style work has created a vacuum of qualified, reliable plumbers. Plumbing is often thought of as low qualifed labor, but the opposite is true. While almost anyone can be taught to turn a wrench or solder a pipe, few take the time to learn the deeper science of plumbing. Water conditioning, purification, recycling water, adequate waste disposal and processing... the list is endless and very much incomplete. Although the work is hard, the pay is very good. I would suggest anyone who has a mechanical intrest, a desire to work, and a good scientific background to consider a career in plumbing.