India Whiskey Charlie[IWC Moderator]
9816
No experience with the latest "in-house" movements but...
I have had many 7750 based chronos from IWC and none of them kept accurate time. The best would be + 10 seconds per day while most of them have been double that. And what's worse they don't get any better after a service by IWC.
Having said that, just recently I had a Porsche Design by IWC serviced by a local watchmaker and so far it's keeping + 5 seconds per day which is quite acceptable to me. So, maybe the key is to have independant watchmakers service these?