Somoene just dropped Kolb to pick up Harden. Kolb was pretty lights out last year, use the waiver priority on Kolb or wait for Kaz?
I guess it really depends on your roster makeup.
Who's your second baseman now? You mentioned that you would switch Reyes over to second. If moving Reyes to second would be an upgrade over what you're using there now, then i think i would pick up Kaz over Kolb (assuming the guy with the #1 waiver spot doesn't take him first).