Brake pads Zimmermann or STOPTECH

To me it looks like brake pad material on your rotors due to your street pads melting. Slap a new set a cheap pads on there from Autozone or something and drive it for a week or two that material should come off. As long as you don’t have vibration while braking they should still be good. Just make sure to use track pads next time. I personally run StopTech 309 pads because they’re good on track and street

I got Stoptech Sport pads that I've used on track and street for many years.

I run StopTech Sport pads on my E92 M3 and they hold up very well for a dual duty pad. I prefer them over the other options listed.

Zimmerman blank rotors are a good street replacement. No need to pay for drilled/slotted rotors. Personally I went with ceramic brake pads. They don’t bite quite as hard as metallic, but they still bite well, don’t make as much brake dust, and they don’t seize to my rotors after they get wet

The StopTechs Sports are the better track and street option, I used the front pads in my E46 M3 for 10k+ street miles and a few trackdays. They have good feel and modulation. Just had a little bit of fade towards the end of a 25 minute session.

I’ve been happy with my StopTech Sport pads.

I've had a bunch of stoptech sports on backroads and they have been good to go every single pair. Dust like crazy but they have good stopping power and hold on to their bite even when they start getting hot. You won't be setting any world records with them but for double duty they have served well.

I run StopTech Sport pads and they’ve been fine. Pretty quiet but also pretty dusty (comparable to stock pads). No full track days in hot weather yet though, just autocross and cooking them on backroads.

The only difference I noticed with Stoptech is more dust.

I purchased Zimmerman pads and rotors from FCP. FCP is fine but the Zimmerman brakes squeal like a bitch.