Accidentally damaging my new-ish Stunner X's Derailleur and the Hanger required replacing both. All bike parts (especially E-Bikes) are scarce and are very difficult to get. I had to purchase a different model derailleur (better, but more expensive) but the Derailleur hanger bracket must be the 'right one'.
I think Biktrix is a great company. I would buy another bike from them without question.
The caveat: I received, from them, a replacement hanger that wasn't the correct one. It was the only one they had listed for my bike; was not sent until I'd spoken with at least 2 Biktrix representatives; was very expensive however they sent it priority/Fed-Ex.
2 weeks from order to receive part that took 3 days to get here. The part was wrong: however I modified it and managed to get it to work eventually. I will ad that while waiting, I did find the exact replacement hanger bracket from 2 other vendors, average cost just over $5 each, shipped. I received them 1 day after Biktrix item came that I'd modified and installed immediately.
The replacement derailleur I had to buy (online elsewhere, Biktrix did not have this) was exactly the same mounting (my new replacement was the Deore model, stock-original was the Aliva model). I'm happily riding again is the end result.
Summary: Hard to get part supplied required modification even tho' it was quite expensive. Biktrix did all they could in light of parts shortages. Even going so far as to upgrade shipping for me.