Just based on posts in various forums, the Excels seem to be a bit stronger than the W9's. My only data point are my two Excel's that have been through hell and back. They do have a few war wounds from my "testing." One thing is for sure, a big enough hit and any rim will get bent. I don't care who made it.
I just can't imagine that there is all that much difference with the spokes, and I'm sure any of those listed will work. Buchanan has a great rep though. You can't go wrong with those.
Now from my experience broken spokes usually are at least partially caused by overly tight spokes. Every bit of excess tension from over tightening reduces the amount of strength that the spoke has. Think of it this way. I have no idea of the actual numbers, but say a spoke has a 300 pound limit before breaking. Proper tightening is 25 pounds. Now what about "proper" spoke vs an over tightened one that is set to 150 pounds in an impact. The proper one can take a 275 pound impact before breaking. The over tightened one only has 150 of strength remaining. In a 225 pound impact one breaks and the other doesn't.
I had spoke breaking problems with my bike. I went over the wheel and found that they were all real tight. I backed off to a more reasonable tension and I've been able to ride for years with no more breakage.
both....
maybe you guys should not put so much water in your camelbacks to cut down on the weight.
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....what am I thinking, this will never happen 
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