Omega Speedmaster - Reduced or Professional

The Reduced's Dubois Dépraz chrono module is fully jewelled, but very few chrono movements have that refinement. Therefore I would be happy to have the chrono running for long periods for my Reduced, but not the Valjoux, Landeron or Seagull movements.

In fact I am so used to having whatever watch I'm wearing having stationary centre seconds hand (aka ready for action) that my new Hamilton's 8 ticks per second still surprises me. Yes, I did video it at 50fps and then play that back at half speed in VLC to count the ticks 🙄

This one exactly the same as reduced:
Omega Speedmaster Triple Calendar Chronograph 3521.80

Apart from the Sapphire Crystal what other improvements are there compared to the reduced.
Would it be a better buy than the reduced if one can’t stretch to the professional.