I went with the Kraken purely for Aesthetic reasons, if you have an NZXT case sticking with the same brand would be a nice detail. If you had a Corsair case then I think the H100i/H105 look so much better than the H110 that it's practically out of the equation. I'm sure from a performance angle they are practically the same as they are basically the same thing.
I still prefer 120mm coolers just because of the greater fan diversity and choice, even though there are more 140mm fans now and some static pressure optimized versions there aren't many different speed or PWM options compared with 120mm so I probably would never go with the H110 or the X61 for that reason.
JR