I could tell very little difference between the two mics, and I didn't hear anything a tiny bit of eq wouldn't level out.
Although I do hear differences in this video, I don't think it's shows the real difference between the two mics. I used some borrowed 609s for a few months for a classic rock band before buying my 906s. I definetly used alot less high cut and other EQ with the 906s(unless the amp tone is bad). The 906s(switch in the middle neutral position) just sound more like the source and less hyped(in a bad way).