Great update/review, the Mark XX is certainly a great watch and it seems you have possibly found 'the one' especially as you can relate to your anniversary.
I too have always liked the 'Mark' series and also picked up my first this year in April via the forum, The green dial XX
It was a shift from the usual dive style watches my collection mainly consisted of and its now one of the ones I like the most and I've since added another couple of Pilot style watches
As much as I like the Green dial, I think I'd wear it more if it was the Blue/black or White dial version, I may possibly a change in the future.
I have to agree the bracelet is a work of art and the micro adjust is excellent, the EasX-Change system is spot on, your Black dial suits them all nicely
having tried a few straps myself as I do like to mix it up, I found the Bracelet suits the Green perfectly so that's all I have now.
For me IWC nailed this one certainly at it's price point, arguably the Date window placement could be slightly better but not an issue for me.