Still flying the harbor cub almost a year now.
I still have the harbor frieght / sdm j3 cub. I was not able to buy a better plane yet! Today I order a brushless motor, esc combo. Let me know if you think this will work. It's a hobbymate HB2806 1650KV & Hobbywing pentium 30A ESC & 2 7x6 props with mounting hardware. The price was cheap $20.50 Motor spec's 1650kv shaft 3.00mm, weight 34g, unload current0.9a (7.4) max current 14.5a (7.4) lipo 2s-3s thrust 530g. I'm running 2s 900 ma 7.4 Esc specs output continuous 30a burst 40a up to 10secs input voltage 2-4 cells lithium or 5-12 cells nicd/nimi bec 2a/5v linear mode max speed 210,000rpm for 2 pole blm 70,000rpm 6 pole 35,000 12 pole size 45mmx24mmx11mm weight 25g.