the 7970 is the best gpu listed, though i'd go with the aforementioned 7950 boost/gigabyte windforce edition... it will overclock up to the 7970, and be the most quiet card you can get.
As to your question, you won't be able to tell any difference in ANY of those titles with any of the gpus you listed. All those titles are CPU bound. which means the cpu will be the bottleneck in the system.
Good thing for you, the i5-3570k is the best gaming cpu you can get, so overclocking that baby will give you a boost of fps in all those titles.