Hi there!
I have found schematics and PCB layouts for each version and the schematics are identical.
The Robotshop picture shows multiple small packages, whereas the Arduino website shows one big package, which I'm guessing is the difference you mentioned.
Most likely, the bigger package has simply combined all of the small packages into one to reduce space on the PCB.
I share your concern that the braking signal sends both motor channels to the supply. Technically speaking this is acceptable, however it is much safer and a better practice to send both channels to ground for active breaking. As such, you may not be able to use this shield if you don't want this braking method.
As an alternative, the Pololu Dual MC33926 Motor Shield is very similar and can be used to power two DC motors at the same time, each with its own direction and speed. Better yet, it has leads to fit right onto an Arduino Uno, but also has leads to control it separately. I would suggest looking into this shield if you don't need the servo and solenoid capability of the Arduino shield.
Good luck!
P.S. I'm new to the forums so apologies in advance if I didn't post the link correctly 