For all CPU VM-based effects, you can take advantage of the attribute debugger. It allows you to see the input values to the simulation as well as the per-particle computed values.

Repeated Capture calls will step the simulation forwards.

You can even capture values running within Play - In - Editor (PiE) by making sure that the system is marked as Force Solo in the Niagara component for that instance.

You can still capture GPU simulation data, but it will only record constants that were set, not the computed values.