Similar to how a pool light should be use a GFI breaker or outlet, the general rule of thumb is it's always best to plug these cleaners into a GFI protected outlet. This is primarily in a effort to protect someone walking across the deck from getting shocked should water be sprayed or splashed on the outlet.
Inground robotic pool cleaners have been around for about a decade and are perfectly safe for the swimming pool and swimmers. Cleaning of the pool cleaners is a snap. Simply uplug, turn over and remove the dirt collecter and empty it. At the same time you're cleaning out the dirt collected from your pool it's also a good time to rinse off the filter elements. They simply slide or pull out. Typically after 3 seasons the cartridge filters inside the cleaner should be changed out with a new one.