Consumer Reports for Siding did a study in 2009 on vinyl, polymer and fiber cements siding ratings.  Most of the siding options below are not available to the Northern California Market, but of the vinyl options we are most comfortable using the Alside Prodigy and CertainTeed CedarBoards based on performance.  The only other insulated siding that we have access to is the CraneBoard, but we have had several warranty claims on that product as it is a large panel (triple 6″ or 18″ total), which we feel is restricting the expansion and contraction.  We have installed a lot of the CertainTeed CedarImpressions polymer shingles and they are by far the most authentic and closest representation to painted and stained shingles on the market place today.

As far as the fiber cement goes, they only rate the primed panels, so I do not think it really applies in this market.  We are big believers in getting your siding pre-painted and James Hardie has by far the best pre-paint program for any wood or fiber cement!  The only product I think Nichiha is promoting in Northern California is their pre-stained shingles.  They do not currently offer a pre-painted program for their lap siding.