I think you’ll find that prices for belt drive e-bikes to be about the same across manufacturers so it becomes a search for what you consider to be the perfect e-bike. IMO after spending months studying the market back in 2020 the things I was looking for were a mid-drive motor, gates carbon belt (I don’t miss oiling chains a bit), geared rear hub of some type (bonus Serial 1 had an Enviolo CVT so no shifting to think about, no derailleur to adjust I really don’t miss that), lights, internal routing of brake lines and wiring and finally really good brakes/big discs as e-bikes are heavy (I want to stop on a dime).
Serial 1 ticked all the boxes for me.
Belt drive e-bikes are built by a multitude of manufacturers across the globe far to many to list.
Good Luck in your hunt for the perfect belt drive e-bike.