I say... KMKIII512H!!! I just bought it, I handled both... the 6 7/8 while it's a beauty also... I went with the KMKIII512H 5 1/2 inch, this one seems more practical as far as handling, more balanced, better looking, middle of the road for size in the MKIII, and will accomodate a Reddot very nicely.
Ordered mine yesterday, get it tomorrow... can't wait to target shoot with it at an economical cost compared to my .38, .357 mag, .45 acp's.... I don't reload, darn is it costly!