Magus--
I thought you'd appreciate my M6TTL & MP compare, and, yes! No nasty zinc. I'm starting to think that Leica WANTS to keep some mystery surrounding the composition of the 999...Not sure why...
Anyway, My guess is you'll love the big wheel, and hate the finder--I'd never had noticed (the finder) as much unless I had an MP and the other RF’s to compare to, but it is a giant difference--It does not happen all the time, but under adverse conditions, it rear's it's ugly head like spitting Medusa.
Regarding the extra height: The BP MP I have looks longer (wider) and shorter (height) --at the same time it looks smaller and less noticeable, and more concealable--all positives for me, but I think it just appears more smaller & innocuous than it really is, because of the black paint.
It definitely looks less noticeable than the chrome M6TTL, which is a very beautiful and classic looking camera on it's own merits.
What I try to say is: It has a very different look, but not a terribly different feel--to me anyway. And what feels different, actually adds to handling. If anything, it feels like the extra height & the big ss dial actually work very well together. While the shorter MP and smaller dial also seem to gel just as well.
I really am impressed with both--once the finder's replaced on the M6 TTL, it will loose it's inferiority complex...! Do you happen to know if the Passport Warranty covers finder replacement? I don’t think I will be able to wait for a cla. I will be looking into this tonight…