First of all, let me say that I have never owned a WE. But from everything I have read, it is a great system. When a professional like Josh at Razor Edge chooses the WE, that speaks volumes.
However, it is more expensive, and I believe that the difference in functionality between the WE and the KME is minimal. Bang for the buck, I think that the KME wins hands down. Also, the customer service from KME is as good as you will ever find. I got the KME set with the diamond hones, and added one of the super coarse hone for re-profiling. If you want more, you can use the strops. I can get a really amazing edge on my knives, and have never regretted my decision to go with the KME.
YMMV, but I would just buy the KME gold kit and skip the chosera stones.