Racers who like Cannondale's handling and want the serviceable frame. Synapse is the taller sibling; SuperX is the CX/gravel race cousin.
The fourth-generation EVO keeps the third generation's geometry but goes lighter, slipperier, and back to a threaded BSA bottom bracket. Same fit as the 2020–2022 bike, easier to live with.
Aero racers. If you want light and conventional, R5; if you want endurance, Caledonia.
The aero Cervelo: V-stem, deep tubes, and a bike that wants to be ridden fast in a straight line and still corners better than its looks suggest.
Climbers and racers who want Cervelo without S5's deep aero cockpit. Soloist is the value race sibling.
Cervelo's lightweight race bike. It does not try to be an S5. Climbing, precise, and still a low WorldTour stack/reach chart.