We used a whole house UV system in Mexico (trash filter, fine carbon filter then UV treatment, we drank the water without problems. That system, combined with a pump in front of the system to increase the water flow/pressure worked well.
Ideal would be the addition of an under sink RO treatment for drinking water only.
We did stop in an RV park where the manager tried to stop us from connecting the UV system (the owner had told him that the system would waste water, obviously referring to the amount of water "dumped" by RO systems). That park trucked in the water. We explained the difference in systems and that the UV system wouldn't dump water and we were good to go.