I can give you the basics (no pun intended):
BM-INFI steel
#9-modified INFI steel (slightly softer, slightly less edge retention. Note though that this is like saying a Porsche 911 is a little slower than a 911 Turbo).
BM-Has the new ergonamic micarta handle
#9-Has respeine-C handle angled at 5 degrees
BM-approximately $349
#9-approximately $204
If you have the money or demand the ultimate go for the BM, if you want an amazing knife at a great price which will probably out do anything you need it to do anyway, go for the #9. Hope this helps.
------------------
"Better to reign in Hell, than serve in Heav'n"
John Milton
There are only two types of people; those who understand this, and those who think they do.