They are very different beasts. Your experience will vary and prepare for some responses that are as subjective as they are passionate.
In my opinion...
Better for the body clock: KA
Better for overnights: CX
Home the family more often: KA
Home with the family for more days in a row: CX
Time to command: KA squared
Salary short to mid term (15-20yrs): KA
Salary long term: CX
Cockpit culture/atmosphere: KA
Gravitas internationally: CX
Annual leave: KA
Control over roster: CX
Etc, etc, etc