Just my oppinion.
I spoiled myself with what I consider to be better knives. Busse, Winklers, Chris Reeves, Spartan Blades, Fällkniven... All of them weak in some respect and not devoid of criticism and/or controversy either.
I had an ESEE CM6 and was not surprised at all, in any positive way. Edge retention wasnt there. Finish wasnt there (grind). Price to quality ratio wasnt there either. Scales were flat and uncomfortable (but a spartan, square design has its own benefits I guess). The knife was ok for its weight, but not excellent or over performing in any way. Not even in the reliability aspect because it didnt keep much of an edge at all (user error?).
The knife was solid, simple ( a plus for me), came with a very good sheath, insofar it was functional. However it didnt do anything my cheaper Cold Steel SRK didnt do, and I would swear and promise that my (much more affordable) Ontario SP6 kept a better edge for longer. Having owned an ESEE and handled many OKC RAT models I cannot tell many a difference between them, and RATs are cheaper and more varied in design. Add the cool custom aftermarket contoured scales for all ESEE models that come in fancy colors and then I would definately say it is overpriced for the performance you get.
Did I get a lemon? maybe (I dont think so). I sold it to someone that would appreciate it more than I did and never looked back at the brand again.
To each his own, thought you'd like to hear some negatives as well.
This was the knife I had: