My experience with about 50 Pierco frames is similar to Lloyd's.  The
bee's interest in the Pierco frames appears to be much less than
standard wax foundation.  I only placed my Pierco foundation within
drawn foundation (as suggested by the manufacturer).  Not always, but
often the Pierco frames were ignored while burr comb was drawn to fill
the space.  Sometimes adjacent frames were extended to fill the space
making manipulations more difficult.  When the Pierco was then finally
drawn, it was very shallow.
 
One interesting possibility - I found that the hive in which I cut
communication holes in the Pierco seemed to be drawn better than the
others.
 
I have not given up on Pierco.  The ease of use makes it very
appealing.  Yet, I have not developed the system for using it
successfully.
 
Larry Krengel
Marengo, IL  USA