I built 3 of these Cubs - one for a friend.
They will fly very well on a 6V speed 400 with a 6x3 and 7 cells.
The stuff that comes with the kit is mostly too heavy for electric.
My first 1/2 A Sureflite Cub actually had a Permax 450. It was ballistic!
After that I just ordered separate fuselages and wings. I made my own landing gear out of thin aluminum. The home made gear was also narrower and used light weight foam wheels.
The rods that come with the kit are also balky. Again I made my own out of 1/32 music wire suported by a sleeve.
The motor can be mounted on a single dowel epoxied into the foam going thru the firewall. Strap it on with nylon ties.
I made the tail feathers out of light balsa with tape for hinges.
Weak point on this model is the cabin walls then the nose.
It can be reinforced.
I never glassed it nor added more than one strip of 2 inch wide tape to the wing. It could probably taped up like a Zagy but weight might be a problem.
I think my cubs weighed slightly less than a pound ready to fly.