160NS is considerably cheaper where I buy film, at least while stock still hangs on. I have only limited experience with this film. Is the color and contrast very similar to 400H? I really like 400H so buying up stock of 160NS might be a cheaper way to get what I like out of color film, assuming the light is strong to make up for the slower speed.
I used to use Fuji 160NS quiet a lot in fact it is one of my favourite color films. The 160NS is Fuji's Portra 160 equivalent not too saturated and quite beautiful for portraits as well as Landscapes. In terms of color fidelity the 400H and 160NS should be close but not identical. If you don't have enough light get a tripod.