RLW, to purchase from United Pipe you do need to be licensed, but for the irrigation design manual I think they'd make an exception. Taking the exam at the DMV can be bad. I had kids running around me, people talking over my shoulder, and enough distractions to make Salem a far better choice. If you like peace and quiet for your exams, go to Salem.
By the way, RLW, I do mostly residential installs and rennovations. And... I have an FC 75 which has served me fine. I'd love the 110, but its heavier, and my arms tend to get tired after a while already with the 75.