They sound so different that I don't even think they should be compared with each other :)
K10 is fuller and more organic while 1+2 is thinner, brighter with more width. Extensions are similar for both CIEMs.
I can point out every bit of difference, but I will save your time here, because if you like one for one type of music, it's unlikely that you like the other for the same type of music :p
Edited by tupac0306 - 2/23/14 at 12:49pm