Using a group of this type of recorders as 'problem locators' can go an extremely long way to saving time in knowing where to pop in the 'big gun' recorder to see what the actual fault is. Note, however, such a recorder still lacks the ability to show you the waveform but it does show surges, sags, and transients (from as short as 4µs).
If you are sold on the "first line of defence" method then these are just the tool that should be employed. It's the ability to measure the current that makes all the difference. In a domestic situation, where the current is likely to follow the load to some extent, these recorders are excellent in locating whether the fault is internal or external to the home. Used in a factory, where the current can be 'reactive' by a few cycles, the results would be confusing and an external fault could lead an electrical engineer to believe there was a fault within the plant.
One needs to carefully choose when to use semi-complex recorders realising the limitation of capturing almost all events but not the associated waveforms.