We have had the Checkpoint system for 4 years now and I have some Cons that
we have discovered:

We place the circuit in the pocket and dis-arm it with the blue 'date due'
card.  It sometimes slips out of the pocket and the alarm will go off when
the student brings the book back, or the student will use it as a bookmark.

If you have several thin items in a stack, sometimes the circuits will
dis-arm each other, making it easy to slip items out of the library.  We
found this out by accident.

If you walk through the gates with the book vertical it will be more likely
to set the alarm off.  If you carry the book horizontal there seems to be
less surface space on the circuit for the gate to pick up, and it is very
likely that you can get the item though.

I took an entire cart of books through a gate one time and the alarm never
went off.  By the same token, when they were moving part our collection
recently the alarm went of *maybe* two-thirds of the time, and that was over
40,000 items moved cart-load by cart-load over several days.

hope this helps

Jody Morris
Serials Technician
National Emergency Training Center Library
FEMA

jody.morris@fema.gov
(301) 447-1354