As a current and recent owner of my first IWC, I'd be interested in this too. OP, out of interest, why the distrust of IWC, previous bad experience ?
The crown on my IWC Ingenieur 3227 only just bites the threads when I screw it down. There's also a speck of something on the dial which needs brushing off. I'd probably have it serviced as well.
I'm not sure I trust IWC with it, I certainly wouldn't send any of my vintage pieces to them. Who do you recommend to carry out work to a high standard using the correct parts in the UK?
As a current and recent owner of my first IWC, I'd be interested in this too. OP, out of interest, why the distrust of IWC, previous bad experience ?
I think Rocco at Watchworks in Bristol does IWC,did very good job on my Mk XII a while back.