If you can occasionally (and safely) use your brakes a lot harder than the average street driver normally uses his brakes, you may find that even '12-level' pads don't have to always be noisy. This may even help maintain uniformity of pad depositing. That's been my experience with the occasional track toy that I've never done the street-pads-to-track-pads-back-to-street-pads swapping exercise on, anyway.
FWIW, I've also found that it's the low-energy, gentle braking events that make the most noise. Probably not enough force being applied against the pads to keep them from doing a lot of vibrating.
Norm