David Mealand is certainly right about different uses for different 
formats of Greek concordances.  But I am puzzled by your comments on
Schmoller, David:
     "...it is not easy to use when you want say 95% of the instances
      rather than just a few typical ones.  Its layout leaves quite a lot
      to be desired for quick consultation, and it is larger and heavier
      thant "hand concordance" suggests."
I do agree that especially in the Gospels, finding references is a little
tedious.  But as for its sampling of word usage, most references are 
complete -- even long ones.  It is true that numerous words are only 
partially represented (e.g., prepostions, and some more substantial 
words like topos, didonai, thelein, and even theos;  the article and 
kai are not represented at all;  and of course there are others).  
But words only partially represented are clearly marked with * , and 
most words are fully represented.  As to size, there is a very handy
5x7x.75 edition that I bought thru UBS.  It is nearly the same size
as NA26 pocket edition, and I "won't leave home without it."  Now surely,
for critical work it is not sufficient.  But for handy reference it is
an excellent resource.  If there is something better, I'd love to 
learn about it.  :-)

Gary D. Collier
University of Denver/Iliff School of Theology