I'm not a fan of Flogging Molly's records but I saw them live and they were pretty good.  DKM are awesome too though - I've never seen them, but you can tell from their live record that they put on an awesome show.  And whoever said the Bosstones beat them both - very true.  I've see nthem twice and they were incredible.  As a matter of fact, I talked to Jonny Vegas, on of their sax players, after the show about DKM and he said he prefers Flogging Molly.