Beyond the obvious advantages expereince brings you have to remember that without using his rings Kilowog has done alright against superman on stats alone.
The Gls are by their nature near even because they all are 1 of 2 (or 4 in the case of earth) of the best ring candidates in their sectors.
So generally unless your a rookie or Hal it comes down to under-ring stats.
Thereby sodom, hannu and Kilowog will take majoirties on most other Gls in the arena.
Kilowog 8-9/10