Well thanks for telling me that bulls! I thought I'd just missed it and it wouldn't be the first time.
One of the best things you can do or have, and that's regardless of whether you go with a whole house setup + a point of use device or just the latter, is a good earth ground. Depending upon your soil and weather conditions, if things are dry and the earth drains rapidly, then the resistance to the ground increases. Now, what's good and acceptable for ensuring human safety frankly falls a bit short of ensuring transistor safety. So, if you don't plan on doing some kind of testing, and that gets expensive, then make a judgement call based on what you know. If, in your opinion, the earth ground can be improved, then you could simply sink another grounding rod into the earth, about the same distance away that the other rod is, and connect the two using appropriately sized wire and clamps. That's something, that if you're masochistic, you could do yourself.
I'd like to be able to recommend something specific to you, but all I'd be doing is imposing my own needs, wants, and prejudices upon you. I think that armed with enough information, you can maybe ask more questions and be better informed whether they're asked here or of the manufacturer. Even though you live in a relatively benign area of the US with respect , I'd urge you to also go whole house. The whole house approach can be looked upon as a perimeter defence that'll deal with all your home electronics (ovens, microwaves, washers, phones, garage door openers, etc.) which you can augment with point of use devices. I do hate to spend people's money bulls, and seeing as you've bought a new house in San Diego, you've already spent a bundle but give it some thought.