K&N filters bad?

[FFGREG32 at aol.com]

I have been informed that K&N filters are bad for my car. I would like to see 
the data on this before I install this filter in my car. I will stay with 
factory filters if the data indicates that K&N filters could allow damage. I had 
never heard any of this before. If anyone could point me to any technical data 
or past discussions where this is indicated, I will be open to learning about 
it. If this is true that it causes damage to our Audis, then K&N needs to be 
upfront about it, or at least hear from those whose cars have been damaged. 
Anyone else have input on K&N? Thanks Greg
1989 200TQ