US does NOT *Net block and they have decent routing rules - not as good as CO but reasonable enough.
I think US has two big things going for it: they consider HKG
and Japan to be "North Asia" (CO does not). That really saves quite a lot on the redemption rates- especially when US will often let you buy a trip involving North Asia AND Europe (stopover) at the North Asia rate.
I also like US's redemption table a bit more than CO's (though the USA->Middle East and South Asia redemption rates are worse on US than CO, USA->North Asia and Australia are better on US, and Europe->North Asia F is only 100K on US, and 160K on CO
).