I assume from your kuk choices you're interested in a weapon more than a tool? The kuk's you're considering are on the light side when compared to an AK for example. The kuk's you're considering would be okay for light chopping but not the best for heavy chopping. From what I have read and based on my admittedly limited experience, the Sirupate, Chitlangi and Gelbu Special, with their thinner blade profiles, are intended to be faster handling, weapons oriented kuks.
I have a Chitlange, Sirupate and a Kobra and, in my opinion, their blade profile would render them less effective choppers. They don't possess much belly.
As Jai siad, I'm sure others will offer their thoughts.