You stated you are using them for survival, can you elaborate?
As for the comparison...
Cutting: Both knives perform all cutting tasks. I have yet to see either knife fail to cut something. Smaller tasks will be more cumbersome with either of these big knives but they do the task.
Chopping: Both can chop well and far outstretched smaller knives but for sustained chopping such as in making a camp, chopping wood for a sustained stay in the woods or largest tasks, the kukri is much better. The weakness most of us have in chopping is our wrist strength. We don't use these muscles very much and after 3 or 4 minutes of sustained chopping you will see most people begin to fizzle out. A straight knife such as a Bowie requires you to flex your wrist and forearm each strike where the kukri, if used properly, uses your bicep and tricep more allowing most people in moderate shape to last much longer. The kukri design, shape, and weight distribution also favor this role.
Hammering: Many of the tasks associated with survival or living in the wild have to do with hammering, smashing or breaking things. In this often overlooked role both knives work much much better than a smaller knife but the kukri has an advantage in this role.
Misc Tasks: Both knives excel at most of the tasks associated with everyday life in the woods, which is why both designs are still around.
I feel the need to point out that saying the word kukri is like saying the word knife. You name a specific knife (Bowie) but use the word kukri and the reality is, many different models of kukri would fail miserably against a well designed bowie while other models would easily outstretch any Bowie.
In the end it comes down to personal preference. For me the kukri (HI Bonecutter, CS Gurkha Kukri, BAS) is the preferred choice for all around use.