Ya I did try that and was not bad, but wanted campaign coop because I played the first one coop with my gf and she loved it. So it was a upsetting to her when the sequel didn't have coop campaign, but she was happy again when Resistance 3 brought that back.
yeah I hear ya!
At the very least it would be nice if Sony remastered the games and added co-op to R2s campaign. That would be a nice bonus. actually a collection with Retribution and Burning Skies with added co-op (offline too) would be quite a cool pack.