Long time lurker... figured I'd finally register to post something...
I'd have to go with Kumba simply because it has been what I've stacked all other normal, looping coasters against since I started riding these things. From the drop onward, it just doesn't really relent. The only real breather section is just before the cobra-roll and even that has a bit of airtime. While it certainly has looked better (didn't they paint this just 2 or 3 years ago?) it's still the coaster that I remember from eons ago. Night time rides plus the fact that with Sheikra and Montu, it never has a line are things that help elevate it for me.
I like Kraken, don't get me wrong... but it just seems a bit familiar. Drop, Loop, Diving Loop, Zero-G... Pretty much everything up till the brake run is Kumba-lite. The little pop of air you get on the far right seat coming off the brakes is fun, as is the use of terrain on the 2nd half of the coaster, but... it still lacks a bit of something that Kumba has.