I have some anecdotal evidence that the Optimus G is a slightly better CDMA performer than a S3, and significantly better than a GNex.
Back to the ingress example, I've been playing a lot with friends, and whenever we go a specific spot in my neighborhood, my LG is able to hold onto a very weak EVDO signal and the game is playable. However my friends with the S3's and the especially the GNex, the game is simply unplayable.