Removal of Methionine in E.coli - (Nov/16/2009 )

Dear all
I am expressing mammalian proteins in E.coli. For downstream applications its important to know now if the Start-Methionine is removed. My inserts are inp pET / BL21 and I use the vector-encoded ATG.
Can I rely that during protein processing the Methionine is removed ?
pET

Methionine can be removed during the downstream by enzyme treatment