After many try and comparison, i'm very interested by purchase B/W plug witch seems to be the more accurate and light and flexible and …
I've excellent results in preview window, but the final file, after pressing OK, look so flat instead the preview …
See this screen capture of 100% crop…
So what the hell???!!
I'm using Mac OS 10.4.6 and CS2, working on true raw .tiff of film scans.
It looks like an ICC mismatch, but it could'nt…
Preview <> Photoshop

NB: in my opinion, the missing feature in this "near perfect" plug is a zone masking capability!
