Hi Leah,
We use NARM at the Rosenbach in Philadelphia and we are happy with it. We offer as part of our membership to our mid-range members and up. So our two most basic levels of membership don't have NARM privileges. We have members that specifically upgrade their membership to get the NARM benefits. So it definitely helps in that way.
As far as how many visitors we get from other museums that use their NARM memberships it isn't many but, we are a small museum. In calendar year 2014 we had about 60 people use NARM memberships.
If I can be of any other help just let me know.
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Alicia Thomas
Visitor Services Associate
Rosenbach Museum & Library
Philadelphia PA
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