Very well said. The analogy is very similar to cars now. The BBSHD is like the chevy V8 crate engine, very impressive on it's own respect and you can slap it to any frame you want, like custom cars or high quality vintage cars. It has its own strong points and its own market.Bosch and Yamaha drives are very sophisticated and they are very similar. They take a small amount of input watts, and turn that into as much wheel-torque as possible. It is accomplished in a very smooth and sophisticated way. This is like the Mercedes, Porsche, BMW market...when they sell a 4-cylinder car (which they have done). Its nice when they are new and under warranty by a local shop, but...if you buy a 5-year-old one? what can an average blue-collar guy do to hack a cheap used 5-year-old M/P/B car?
I am an old gear-head (58-ish), and as a much as I appreciate a sophisticated aluminum 4-cylinder turbo 4-valve engine with EFI...when it comes to buying and wrenching on a motor? the BBSHD is the Chevy 350 of the Ebike world.
If a certain customer is like an engineer, and he wants decent wheel torque at the lowest possible input watts...get the Yamaha mid drive. If you want LOT of fun, and you also want the ability to upgrade your fun-result in the future? Get the BBSHD. Also, get a spare primary reduction gear and a tube of high-quality grease, because...I am going to beat on mine like it is a rented mule. Try 2600W on a cheap drive unit and then tell me that it doesn't put a freakin smile on your face...
However, the integration, overall durability, factory backed warranty, overall performance, and especially, the energy efficiency (how many miles each battery charge can provide) attract the huge remainder of the market to the OEM side.
Different strokes for different folks. Each have their good points to say and their own tastes to satisfy upon.