Looking for an conversion kit and battery under a total of ~600 USD

[PedalUma]

I agree with the 'foolish' reviews that appear on Amazon. Like someone trying to remove a hub-drive axle nut with a cone wrench and whining that it broke. I just did a Tannus job on a fat tire hub bike this morning - what a pain to ever remove the rear wheel. The bike weighed a ton. No wonder most bike shops won't touch them.
My group ride did a nice sustained climb ride yesterday to the top of a mountain in Norther California up into the fog line. We could do it because there were not any hub drives riding with us.

 

[indianajo]

I live near the top of a 1100ft mountain and the climb starts near sea level. My no name geared rear hub motor gives excellent assist on this as well as other hilly routes and has never felt hot even after a long pull. Neither my TSDZ2 mid drives nor my Yamaha PW-SE drag.

geared hub motor windings do not touch the outside. That is the problem. Glad the no-name brand you bought can handle 1000' rise.
Knew Yamaha didn't drag, also brose & shimano steps. 90% of posts on this forum are about bosch & bafang mid drives. Only the most expensive bosch doesn't drag unpowered, IMHO.