I don't own any ATs but like you I much prefer the older ATs, and the 371928 black dial day-date-chrono complication with the 12 to 3 o'clock white band is among my top 3 favourite ATs. I agree with your sentiments on greater elegance and more in line with the even earlier-released ATs.
On your question on the IWC/ETA movement issue, I believe the answer is:
"[b]Now, what does IWC do with this calibre, and why do they treat it as if it were their own movement? The explanation is pretty simple: IWC purchases the best serial engine and undertakes on that basis the best possible engine tuning. You could say that IWC does what AMG does with Mercedes engines, Alpina with BMW or Abt with VW or Audi engines. Serial engines are used, which in turn are tuned and optimized with the best experience available.
In the case of the Valjoux, the calibre is only bought in its components, never readily assembled. In addition, only the best possible version is purchased - the so-called Chronometer version. When the components arrive in Schaffhausen (IWC's factory location) there are first of all checked by eye, and then randomly checked in detail. Some components of the original ETA calibre are immediately eliminated and are never used by IWC. They are replaced by usually more expensive and better ones.[/b]"
from this article.
In case you wish to know more about the IWC/ETA movement issue, you may wish to consult this earlier discussion, and also the links referred by Bill here in this other post, which I find most useful. I also agree with Bill's sentiments in this quoted post.
Of course, there valid arguments on both sides of this coin.
