An indepth look at the ETA 2892

I found this article about the ETA 2892 interesting as it's the base movement of several IWC models. I know IWC takes a lot of criticism from people with emotional (I've never seen a critic offer technical arguments) preferences for in-house movements. I'm not technically skilled to judge the author's credibility but going off his review, the ETA 2892 is a very good all-round movement. And I have no doubt the IWC required modifications improve it further.

www.chronometrie.com/eta2892/eta289202.html

And here's one from the same author with some comparisons with the ETA 2824:
www.chronometrie.com/eta2824/eta2824.html

Very good article, and it highlights the weakness of the inhouse calibres in general: Except for Rolex and maybe Zenith, none of the manufacturers built calibres in the quantities and steadily over time as ETA did. This experience they have can't be matched.

It's interesting how people with no technical understanding of the movements seem to assume an ETA supplied one is inferior in quality to an in-house movement.

While I don't share them, I can understand and respect any emotional preferences some people have for in-house movements. But in terms of accuracy and reliability, you can't really question IWC's decision to stick with the ETA 2892/A2 on their simpler watches.

If wishing to choose a daily beater I'd prefer anytime an ETA-based IWC to an in-house one, that's why I'm very happy that my Aquatimer 376706 is based on the ETA-Valjoux 7750 and not the 89xxx: advantages are reliability and accuracy, less expensive watch, cheaper and better long-term access to spare parts, not to speak about the weekday feature and the 30 minute counter which is more traditional than the 60 minute one and way more easily readable for short intervals for my aging eyes. I only miss the fly-back feature.
Just my personal opinion of course, no offense intented. If some day the 89xxx (12 hours chrono) will be extended by a simple full calendar or a weekday feature and find its way into a normal size steel Aquatimer case I could hardly resist...

I'm not a chrono guy but the hour and minute totalizer versions with the 89361 calibre are special. The 3878 Pilot is one of my absolute favorites. A perfect cigar lounge watch.

In regards to IWC I'm more wondering if ETA or Sellita is being used in the entry models and what difference it makes if any.
I can't find more information regarding this topic. For example is the new Aquatimer automatic ref. 3290 using modified Sellita movement ?
My understanding is that Sellita is pretty much leveraging original ETA designs and their parts are interchangeable with ETA.
Assuming both are the same cost to IWC, why would IWC pick Sellita over ETA or the other way ? Or is it just question of availability of these mass produced movements ?

My understanding is that the 301xx calibers (ref's 3239, 3265, 3290, 3557) are ETA-supplied 2892/A2 made to IWC specs.

As for Sellita, IWC has a partnership where they have jointly developed an IWC exclusive movement named the Grandjean movement. But I haven't seen any information on which IWC models use it. My best guess on IWC's reason for partnering with Sellita is to secure availability. With multiple capable partners that can supply movements to its quality standards, IWC is less exposed to risk of supply issues.

Very little of the above has been officially confirmed by IWC so please note that this represents my understanding from different sources of information and may not be 100% correct.

IMHO the "Valjoux 7750" chronograph movement variations are marked differently: cal. IWC 79xxx is based on the ETA version while the 75xxx is based on the Sellita version. So e. g. AT chrono 3767 and 3768 use the ETA, Portofino chrono the Sellita movement.

I think the disdain for the ETA 2892 that some "connoisseurs" have is a function of marketing rather than technical merit. I know people speculate about how IWC "modifies" the ETA 2892, but to me, I hope they keep it as standard as possible. A complete "in-house" movement is somewhat of a liability for the watch, in my opinion, because it leaves you locked-in to the manufacturer forever for parts and servicing. The result is that the big brands can charge huge sums of money to service their movements because you cannot get the parts anywhere else, and thus, only the manufacturer can service it. This has been going on for years, as the big brands like Rolex, Omega, etc., have been cutting off independent watchmakers from the supply chain for replacement parts and tools, and at the same time, have been trying to convince the public this is good for them.

With an ETA 2892-based movement, any good watch-maker can service it and parts are readily available. On the other hand, with an in-house movement, you're not only locked-in for parts and service, but if the watch company goes broke, your expensive watch will transform itself into a paperweight the next time a part breaks. People may think that's unlikely, but recessions come and go, and so do luxury brands. If you love your timepieces, you'll keep them for decades or longer, and that's a long time to hope that that the maker of your "in-house" movement stays in business.