I think the Hi boy was of its time and heavy although did from memory not suffer from the dreaded flat bottom wing section.
Although I agree that electric is the way to go nowerdays for a trainer there are not, to my surprise many balsa bespoke electric trainers available. I have however discounted many as for me shoving the lipos in from the bottom of a IC trainer design like many have done is not an electric trainer. I hate to see new flyers having to turn the model over to make it live and then having to turn it upright to fly.
Anyhow I am about to build a bit of nostalga in the form of a Kamco Kadet and would recommend it strongly.