Definitely go for the Robbo. You wont be able to learn on a Scout unless you buy one and even then you may have to get your ppl on a non permit to fly a/c.
Robbos might get a lot of slating by many, but you'll be surprised at how many ex mil instructors who have time on the robbo rave about it. Learn to fly Robbos and you can fly just about anything. Besides it is easier to get hold of a robbo to hire, they are more reliable than a Scout and they are much quieter. Also as yourself why someone is trying to sell a share in a Scout - because it is too expensive to maintain???
Buttline is right - go for it in an intense course but get an instructor who will finish a lesson and send you home if you are having a bad day. Shop around and see what sort of a deal you can get - most training prices in the UK are negotiable
Good luck, fly safe and have good fun