Yeah saw Gallows at warped last year, they put on an awesome show. And they also are kind of cross over, somewhere in between hardcore punk and metal. It's a nice sound.
Don't care for ADTR at all though, when really I should love them considering they take the best of both worlds (Metalcore & Punk) but they just don't do it for me. I prefer straight up metalcore bands to them for some reason.
Anti-Flag is another goodn' Currently I am waiting for December to roll around, The Adolescents are going to be playing a show in my city....and that is never going to happen again, so I need to get tickets soon.