G'day,
the new ref. 25820 and some ladies models sport a column-wheel chronograph movement.
All three-register chronograph, including the R&D, Laureato and WWTC, make use of a chronograph with a cam/lever construction.
In fact the difference is hard to tell from actual use. A well constructed and built cam/lever chronograph doesn´t have to feel different.
Cheers,
Peter