I will say though, buying the controllers or motors straight from China is cheaper by a factor of 50-80%, and allows you to get more headroom. Though I wouldn't trust Chinese batteries, and shipping can be slow.

It's a different price for a different product. Grin Technologies does their own design, and makes great stuff.

Not for the motors, and the Grin ESCs are not the only ones available. In any cases, Chinese Kunteng ESCs are also very well made, with an open-source firmware available and provide pure-sine wave control as well as regenerative braking for less than a third of the price of a Grin ESC, and also have headroom (people have been overvolting them by significant margins without issues).

Yes, Grin has its own custom motor designs.

Yes, and they are pretty bad. For the price of a Grin motor you can buy a much better, fully custom QS Motor with components and windings of your own choice, and have enough money left to buy a second one. The Grin motor will be slightly lighter but will also overheat earlier, so there's really no advantage - you can just get a smaller motor and push it harder. Nothing is free - Grin motors aren't really better than anything out of China and for the outrageous price they sell at you can literally get a motor custom made.

How can something be 150% cheaper?

Ah sorry, I meant the reverse, that Luna cycles is more expensive by 50-150%. Will fix.

Justin from a .ca website: nice.

He is also really active on some of the ebike forums.