Why would one need a UV if there's also going to me actual filters after that? (honest question) Only thing I can think of is to prevent contamination of the filters.
It is entirely site specific. I don't have any filters, just a water conditioner (since I don't want to deal with a softener). Adding UV would probably be unnecessary but would provide some nice peace of mind.
Because if you have an actual filter that is a small enough micron to capture pathogens, it's also going to capture all of the really fine sediment and plug up quickly.
