Interesting watches these, with an interesting function.
I'd never have guessed that there were this many discrete versions (not having looked at the Seafarer section in some time, which is a bit of a strong clue that there would be this many!).
For me, the 2443 case is most interesting because there we can begin to see the genesis of what was to become the Carrera case (check the details of the lugs compared to both the earlier watches and the later 2444 case).
It's good that there are still niches like this in the Heuer world that we can uncover.