Let's examine the excellence of E+, BionX and Tidal Force and the rest of those "excellent" companies. They only had one problem - they lost their ass and went out of business. My cheap Chinese hub motor and mid-drive still hum along after four years and the companies are still in business. I shouldn't need to, but can get parts for them if they ever need to be repaired. Now the "dinosaurs"; if you're ever unlucky enough to find one, just try to get parts for it.