IWC watches

I am considering purchasing an IWC Spitfire Chronograph and am curious
about the calibre 79320 movement. Is this a reliable movement? I also
wondered whether this is an inhouse design or a modified ETA platform.

I am slowly getting into collecting. I currently have a Zenith El
Primero Chronomaster. However, it is currently in the shop which has
inspired me to look for another watch. Any information would be
appreciated. Thanks.

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