I have used Pierco brood frames for some time now.  One problem that I have
not seen discussed is due to the excess bee space when a brood chamber of
Pierco is placed beneath a chamber of wood frames.  When trying to separate
the two brood chambers burr comb holds the Pierco frames, making them lift up
off their frame supports. This causes difficulty in lifting off the upper
brood chamber.  I have to insert the hive tool and pry down the Pierco
frames, while holding up the brood chamber with the other hand.  This is
awkward, and often the bees do not like it at all!

Ted Fischer
Dexter, Michigan USA