JP
I flew the JP straight after finishing my PPL on a C150 in 20 hrs. It is not difficult to fly, they let 19 year olds like me loose on it. It is a bit different to a PA28 but it is actually easier to fly, it is and flies like a classic aircraft. You do have to manage your energy, but all aircraft required that then, that is one of the skills.
It is basic and straightforward and a delight, I loved it and would love to fly one again.
Go do it and make sure you do not get tense and just enjoy it and I promise not to be envious!
MM