I haven't tried it in a band situation but I'm sure it would be fine. It's very loud. I've seen posts on this forum where people are using it live and they say it works well. See this post, for example:
http://line6.com/support/topic/23337-laney-irt%E2%80%93x/?do=findComment&comment=207530
Like I say above, it's brilliant with the Helix and I'm buying a second one for stereo effects.