Ron_W
1636
Hi Jurry, what a great idea for a gift to your son. I own several IWC watches and used to won a speedmaster so similair taste as your son. Older physically but 30 at heart...
If it is a watch for business/dress the Reverso tribute Night Day moon 2017 is one of my favourites

or the Original version posted here earlier by another member , ref 273.8.85 if i am not msitaken. JLC has many versions with different ref nrs..
there is also a version with large date and/or moonphase.
If it is for more casual/sporty this is a killer chrono , tribute to deep sea, the 2 register ref Q207857J is my favourite of the 2. there is also a memovox alarm in this serie 1 US LeCoultre version and 1 EU JLC version. But the latter are limited series so difficult to find.

Good luck with this task !