I have a 2003 and it was a little bit much power for him with the stacked washer clutch. I changed out the washers for springs from a mini adventrure and it is perfect for him. I will probably change it back to the stacked washers in a couple of months once he is used to it.
A 2000 pro junior that is in decent shape is probably worth around $700-800. So I would base whether it is worth it on that amount.