Cost being no issue--and apparently not, since you're also considering that high-end 18 kt. gold plated vinyl siding--HardiPlank is the clear winner.
HardiPlank vs. Vinyl Siding: Factors to Consider
- Thick or Thin? - HardiPlank has actual thickness. While thicknesses do vary, an average thickness of HardiPlank is 5/16", or over a quarter-inch. Vinyl siding is mere millimeters thick.
- Non-Combustible vs. Burns Like a Match - HardiPlank is composed of cement-like materials. Contractors complain because the stuff kicks up clouds of cement dust. But their pain is your gain: HardiPlank doesn't burn; vinyl siding does.
- Nearly Real Texture vs. Laughable Texture - The other interesting thing to note about HardiPlank's thickness is that this allows for deeper impressioning of texture, so that it looks like wood. Vinyl siding is too thin for any kind of texturing.
- High Cost vs. Lower Cost - In the event that cost does become an issue, then vinyl siding wins out every time. Not only is the material itself cheaper, but labor is cheaper.