Well they make a difference on 30+ pound planes ! Plus I'm really starting to have fun with them after some practice on smaller planes. Ultra Stick with quad flaps doing short field take-offs and landings, diving down with crow and almost helicoptering in for a landing, slow fly-bys . Even on the new 60 size Meridian I'm having a blast with the flaps.
I would say again to rebuild the plane after looking at it.
With a non-computer radio you may have had too much throw by using the lever. Would have to limit max throw mechanically and find out how much flap it can handle by testing it up high going slow. You might have to manually input some down elevator when coming in until it slows down enough.