I'll answer the last questions
Being thrown in and out of a van (not literally) they seem to survive okay i.e. pretty robust.
Cooling is usually pretty efficient. I say usually because the air intake is at the top so if you put it in a flightcase, you have to leave at least a 1U gap at the top to allow for airflow. Put it in a 2U flight case and block the air intake and it will overheat.
Soundwise, the DA series lack bottom end (and probably aren't as powerful as they state for full range). I have done a side by side comparison with a Warrior DA and a more upmarket amp of about the same power (actually it was less) and the more upmarket amp was louder before it started to clip and gave much better bottom end (Warrior bass was more of a "phut phut" compared to a more upmarket amp giving a "boom boom").
They may well be fine for bedrooms or a small rig (depending on speaker efficiency, I probably wouldn't use one on its own for more than about 60 people). The one I used was very easy to clip without seeming to be very loud.
Im still debating if its more helpful then Maxs'