CO OnePass and NW WorldPerks are essentially identical in terms of benefits. On the non-benefits side, it's a fairly universal belief around here that WorldPerks customer service is significantly better than the OnePass service center. The main reason I think that OnePass won awards instead of WorldPerks is that CO's in-flight product is generally etter than the equivalent product on NW, which isn't technically what these awards are for, but it's a natural association.