I have a suspicion, that BMW knows about this issue. And I guess they will not do anything about it. We are the minority of M3 drivers here. I estimate about 10-15% of all M3 drivers are on M3post.com, and even here maybe 20% tracks their car regularly. That's 2-3% overall.
What we could do, to ask AA or any other tuner to develop a kit heat shield. I would be happy to pay $100-200 to have this fixed. Also would happily pay for the break cooling ducts (but not $600!!! just for intake without plates, ducts etc.)