Looking for a good meter for us to carry was a nightmare - couldn't find anything I liked. And I asked someone who owned a light measurement company to advise me, what I found out about the quality of most available meters was horrifying.
If you buy the Pentax meter, it won't be any good for color work, or Polaroid Black and White. Polaroid is wildly sensitive to ultraviolet and the Zone VI Pentax won't read that. I spoke to a Pentax tech guy about the modification too...
If you want to e-mail me directly I'll give you specifics. I don't like to mention other manufacturers on this forum.
There is a lot of discussion about spectral response and meters in our E-Newsletters and I'd be glad to send them to you if you like -------------- or anyone on this forum.
Anthony Guidice, Fine Art Photo Supply