I use a Severne NCX 8.0 and a Gator 6,5 on my k105.
Despite the fact that the 8.0 size has been proving to be bigger than the board can carry, I would consider the NCX model. It has incredible power, confort comparable to a cambered sail, yet keeping light weight and the ease of a no cam. I'm planning to change the 8.0 for a 7.5.
The Gator has about the same power than the NCX. The only difference is that it feels a little more "rigid" (due to the x-ply, I believe). For the "big sail" on your kombat, oriented towards freeride, I would recomend the NCX.
I'm also curious about the Ezzy Freeride. Anyone has any quote on the sail?