Irvine Ranch WD has the worst water quality per our plumbers though all of South OC has terrible water quality which leads to pipe corrosion and copper pinhole leaks - you can see the blue residue which we did when we did the PEX repipe and Halo 5 whole house water system after we sprung a leak in the kitchen ceiling. Highly recommend spending the $5K for the Halo. Water tastes awesome and it’s alkaline.Plumber I used told me his Newport clients have whole house RO systems, I guess they’re keen on risk mitigation.