@neilpriceart my iPad is about a couple years old, it works fine. In my opinion, it is not an essensial tool in my current process, more in the category of things that "nice to have". I got it while my girl was a new born, so I can draw in bed.
For artists who do art on the side for fun but have a full-time job on something else, I might recommend to start with iPad, becasue it is so easy to carry around. You probably end up doing more drawings this way.
For artists with a limited budget to set up a workspace for making illustration full-time (especially, working with books), I would recommend starting with a small cintiq + a computer instead. You can always add a ipad once you get a few illustration gigs, and set money aside.
Hope this makes sense.