I think the Butterfly was a great trainer. I didn't have one. But I did see other people with them. And a couple of people let me fly thier Butterflies. I thought it was wonderful. But I didn't build it. The people that did build them generally had no previous experience and theirs turned out alright.
Gliders and powered gliders are entirely different animals from the regular powered airplanes. Things happen so much slower. And since it is best to have an instructor with you anyway, you might consider going with a conventional trainer type airplane.
Now, if you out on the farm somewhere with no one to help you, then the Butterfly is the ticket. You will crash it. But you stand a better chance of success with the Butterfly than with a faster trainer type.