I guess Scottie hasn't posted back in this thread in awhile, eh? I know him from the 745i boards, when I was on them a few years ago, with my '85 745i turbo. He had a phenomenal setup for them, back then. I can only imagine what he could/would do for the M42, given the time..
I, personally, want to go Speed Density. One day, maybe I'll start on my SMT6 w/MAP install/conversion.. I want to go turbo, so I'd prefer SD over metered intake system.