Yeah I know SO4 and FF13 are very different games but I can't help but compare them as they are both the newest JRPGs I've completed, they are both the first JRPGs I played with my respective next-gen (well, last gen now I guess) console and they're both from different parts of Squeenix.

As I already covered the Eng dub for 13 is better and so is the overall soundtrack. The problem arises in the fact SO4 beats it in every other way. Despite the fact you travel to several different worlds, each of those worlds feels more vibrant and alive than anything in 13. SO seems to excel at world-building and SO4 is no exception to that.

Someone elsewhere said the writing was better in XIII but I dunno. Some dialogue was pretty bad in SO4 but XIII gives us Lightning and Hope discussing the symbolism of their names and that is an almost uniquely grievous example of bad writing.

Overall I just found myself liking the cast more in SO4. The Private Action stuff really draws you more into teh group dynamic than anything in XIII.
And the plot...pft, what plot is there in XIII. It doesn't make sense and it's poorly implemented. SO4 kept me interested from start to finish, never relenting on providing new questions to be answered.