Bosch is a multi-billion dollar corporation that manufactures its own auto ignition coils. It does everything from mold the body, mold the coil bobbins, stamp its own metal parts, mold its own rubber parts, wind its own coils, assemble all of the components and test the final assembly with high voltages. This allows them to closely control their manufacturing processes and in turn quality.
Can as good, or a better coil be made by others? Absolutely, as long as that other entity uses equal or superior materials and controls their manufacturing processes. I doubt Bav Auto runs their own factory assembling product. They purchase from a third party manufacturer, and have no direct control over the product they buy.
Names like Bosch, Bremi, AC Delco, Delphi, Champion have been around for years and have developed long standing reputations for quality product. BMW uses Bremi and Bosch interchangeably for their OE component ignition coils.
Maybe in twenty years the Bav Auto labeled coils will be considered the best in the industry, but for today I would stick with a known name like Bosch.