Hi Tom, welcome to the forum, good luck with your Rib buying and if you need any advice this is the place to get it!
I did my level 2 powerboat course a week ago with Plymouth Powerboat School courtesy of their instructor Michael Whelan (01752 873087) I used my own boat which may well be an option for you as well. Not only did I learn a lot about boathandling but also about the boat itself and the waters in the Plymouth area, really enjoyed the course and wouldn't hesitate to recommend it or the school.
Best of luck
Kernow