Complex sentence: Radio clocks, radio controlled watches, and atomic clocks have made mechanical clock-chronometers obsolete for time standards used scientifically and/or industrially, although most custom watchmakers still produce them and are considered status symbols when produced by the likes of Rolex.
Split into simpler sentences: Radio clocks, radio controlled watches, and atomic clocks have made mechanical clock-chronometers obsolete for time standards used scientifically and/or industrially. Most custom watchmakers do still produce them, however, and they are considered status symbols when produced by the likes of Rolex.