So far 203 is seeing no difference.
When I did tests with two different MF backs (Hasslblad and Phase One) I could see no difference in shadow detail when compared to the Canon 1Ds Mk3.
Has anyone else out there conducted careful side-by-side comparisons?
As I mentioned on page 4 of this thread, I've compared my P45+ against my D3. The only advantages I see with my P45+ is the total number of MPs, and the lack of an AA filter, which together yield crisper, higher resolution images. I see no real advantage to the P45+ on shadow detail retrieval and color fidelity. Specifically, here's what I said:
"In 14-bit mode, the D3 has tremendous ability to pull clean detail out of the shadows without suffering posterization and other artifacts. In that regard, I'd say it's on a par with my P45+. And the D3 actually has a little more highlight headroom than my P45+, so in that sense, the D3 is actually a bit better (tho again, the difference is slight). If the D3 sensor didn't have an AA filter, I'd say the pixel level quality would be a wash."
All that said, the P45+ is always going to be my first choice, because it does have the MP advantage and the lack of an AA filter. Those are still huge advantages, in my opinion, that can't be ignored, and can only be approached, with considerable limitations, using stiching.
This whole business of shadow detail and color has become a red herring, I think, at least when it comes to the latest generation of high end DSLRs (D3, 1DIII and 1DsIII). These new high end DSLRs have true 14-bit, low noise A/Ds, and for all intents and purposes are "just as good" as 16-bit sampling that you find in a MFDB, or at least so close in quality that it's virtually impossible to see the difference.