The goal of penjing is to
capture the mood and spirit
of nature's scenery.

The goal of saikei is to
accurately represent nature's
scenery.
I sometimes have difficulty
deciding if a scenery is
penjing or saikei.  So I made
the word penkei to use in  
such cases.  A google search
revealed that Penkei is the
name of a city on the north
island of Japan.