Comparing a power source consisting of "ultracaps" with a regulator based power supply following aspects should be taken into consideration:
- Unless a load draws a constant current (in which case the supply will perform perfectly anyway) one is not going to get pure DC out of something that doesn't have 0 output impedance. That's why:
- A regulator will give "purer" DC then "any" amount of caps will, unless one has a very, very huge amount of them in series/parallel to match the impedance and voltage upkeep capabilities of a decent regulator.
- The capacitive reactance of the capacitors can be an issue (or a benefit) if one don't connect enough of them in parallel operation.