It's a situational weapon like every exotic. I wouldn't bring icebreaker into a mission that's mostly close quarters, I would bring a hand cannon. If it's close quarters with a mob of enemies rushing me I would bring hard light. Only time that calls for ice breaker is an open area where the you have time to camp and line up shots. The only weapon that is the exception to these situational rules is hawkmoon, that gun is good in any situation.