Yup they'll be workin with the magic controller
![Wink ;)](https://goldenmotor.com/SMF/Smileys/default/wink.gif)
they are BLDC
![Cheesy :D](https://goldenmotor.com/SMF/Smileys/default/cheesy.gif)
Not sure of the build quality, and the type is pretty common. They look like enamelled Unite motors
cn-dcmotors.com but have better dimensions.
Seemingly, you could use the 500W model for a mid-drive, any bigger and you will need to change the crank axle width as the motors become quite large.
I have a Unite BM1318 which looks similar to the middle GM one in the picture. It is a behemoth of a thing and I would not be thinking about using it for a mid-drive... It also weighs 6.5Kg and that is only a tad less than a complete hub motor wheel assembly...
If you have a tricycle then awesome!! That's what they are intended for anyway
![Cheesy :D](https://goldenmotor.com/SMF/Smileys/default/cheesy.gif)
Maybe if I was a few decades older I would build a quad-drive tri-cycle with 3 x MP's (cast of course) and one of those chunkers connected to the rear axle for some sideways action on the way to bingo
hehe