I had chance to try shimano, bosch, bafang and brose.

I gave my comments.

1- Bosch : Nice motor but for me they look ugly with those batteries. Had good aftersales service and system. Love their diagnostic tools. But for me most e-bikes use bosch seem like so ugly.


2- Shimano : Smooth ride but don't expect much power. Thats what i felt.

3- Bafang. Don't ever try to use it. ( i know your question was for shimano vs Bosch but i wanna mention ). Not a smooth ride. I would prefer to spend couple more bucks and buy something reliable.

4- Brose : Mate i would advice you to buy brose. They seem more flexible about battery pack design. I see some brands use different batteries so aesthetic point they are superior. Don't think i am a shallow guy but if i am spending over 3K i would want my bike to look nice. I am now little bit shy on money but on september during sales time want to buy one.

THeir performance seems better.
After sales : I am not sure but diagnostic systems seem same like bosch. Sure bosch must have a wider coverage of AM.

The ones i know who you use
- BH: Nice battery with brose system. Really nice nice bike
- Ariel Rider : More like a cruiser bike but seems to have better performance. Also have a comfortable riding position
- Specialized : That machine look like a beast. But so expensive for me.