Quick take
ITEHIL is interesting for RVs, travel, emergency backup and temporary living situations where higher-purity water matters more than ultralight portability.
Where it fits
A powered portable RO system can make sense in RVs, temporary housing, offices or emergency setups where the user wants membrane treatment without installing plumbing.
It is much less convenient than a bottle filter for hiking or daily commuting.
Tradeoffs
RO requires pressure and wastewater management. In a portable appliance, that means pumps, electricity, tanks and proprietary filters.
Those components improve treatment capability but reduce simplicity.