I remember when I was running the Biology Library at Temple University.  We
had hinged front display shelving with journals lying flat on the shelf
behind.  My real problems were 1) biomedical journals that were thicker than
the shelf lip and thus quietly self-destructed, 2) the problems patrons (and
I) had holding up the upper shelf with our heads while rummaging for a
back issue and 3) coping with stacks of slippery journals that fell on our
feet while we rummaged.  I much prefer flat shelves with journal spines out
for *access* -- but there is always the problem of finding the issue in the
first place -- scanning the labels on the narrow edge of the shelf.

A related shelving issue -- a government agency which shall remain nameless
wanted to get some new shelving to store reports, books, photocopies in folders
, etc.  They were sold a  *marvelous* system of modular shelving units that
(as I recall) consisted of horizontal ranks of vertical "binlets" that tipped
forward slightly to facilitate access.  The problem was that no-one (including
the staff and consultant) apparently physically matched what was being stored
to the shelves themselves (bought through a catalog?). Books, ring binders
etc didn't fit and papers flopped. I suspect that thick journals might have
worked, as might papers in stiff folder bindings.  Sometimes the old ways are
best.

Kate McCain