Welcome to LaLaLand
I live in Playa del Rey, just north of Los Angeles International Airport (LAX). Power here is stable except for during some thunderstorms. I have not put a meter to it but I do not get the kind of strobing and flickering you describe. As a life long resident of LA I can tell you that what you are experiencing is anything but the norm. My guess is that it is highly localized.
I do run an Equitech on my 2 channel system and a small Balanced Power unit for my HT rig. The HT rig uses Harmonic Tech PCs that Jim updated with the latest Furu stuff. The 2 channel rig uses a combination of Whale, VH Cryo 4 and Stealth PCs - no method to the madness, just madness =) Both conditioners are plugged into Porterports.
Through some bizarre luck, the people who built this place put circuits everywhere - so effectively I have a dedicated 20a circuit for each rig. In addition, the computers are heavily isolated through APC UPS back up units
Only real complaint is an intermittent squawking which i attribute to some security type at the airport keying a mic or using radar. I talked to my ham buddy across the street and he gets exactly the same thing. Nothing gets rid of it - for what its worth it shows up least in the BPC system
best,
ck