Digital SMPS Vs. Analog SMPS
These are my general thoughts: -


Easiest - power management IC (PMIC)
Smallest footprint - PMIC usually
Cheapest - usually PMIC (for a certain minimum performance level)
Highest performance - PMIC will outshine all others
Best reliability - PMIC
Best stability - PMIC
Quickest reaction time to load changes - PMIC
Quickest reaction time to incoming voltage changes - PMIC


And now the bad things: -


Unreliability - microcontroller
Instability - microcontroller
Noisiest - microcontroller
Poor reaction time to load changes - microcontroller
Poor reaction time to input voltage changes - microcontroller