The $85 dollar "bling ring" upgrade option from EM3ev is a must have. The BBSHD default ring performs poorly and has frustrated reviewers by repeatedly dropping the chain. The default also weights twice what is should.
The BBSHD chain fall off problem does depend on the type of bike. Electric-fatbike.com has a article with the details. I noticed hyperlinked clicks to articles on their website usually get a error message. So the easiest way is to go to the homepage, then scroll down to the article titled " Finally, A BBSHD Chainring That Doesn’t Suck : Luna Eclipse ". The chain slip off problem is detailed there. Not sure why the size of my post text is changing. It is not intentional.