Hi Gabby............. do BMW recommand sintered front and rear..
Any other machine I've owned recommended that if sintered were on the front they should not be on the back to prevent the wheels locking........ perhaps BMW with its ABS is different????
Always except one round of EBC’s had them front and back. Locking the brakes depends on how hard you pull (and press the levers) and conditions! I have noticed no differeance between the sintered and standards on how they behave...sintered cost more and last longer and that's it from my normal riding experience.
Think of a race bike with carbon disks and high spec racing pads......they work without locking up (mostly!). All down to how you use the brakes. Got crap brakes pull levers hard...got shit hot brakes pull levers gently!
I did Cadwell Park last year on my R1200GSA with sintered back and front,....nothing locked and believe me I was braking very friggin hard! Much harder than I ever would on the public road and never got out of shape once.
Get out there, on a dry day, on an empty road and try braking as hard as you can (or dare) you will be surprised and I bet you won't get them to lock up.
I understand that ABS only comes in on the final 25mph anyway.
I found normal’s on the back just did not last long enough and screwed up a disc as a result....failed to check them soon enough and scuppered it.
Your choice and do what your comfortable with. Both will stop you just as well.