Another vote for Dynalite here. I *abuse* my strobes (I shoot hard and heavy), and they hold up like nothing else outside of the very expensive top end gear. I got my first dyna pack in 1998 (I own a few), and in 2010 I finally had to send it in for service as I blew a cap - I wouldn't be surprised if it had nearly half a million frames on it across those 12 years. So over time, I've found their stuff, while definitely NOT fancy and modern in any way, is quite robust.
As for safety: I don't think I ever yanked a cord without powering the unit down (I remember stories the late Terry Bollman at RIT used to tell about people getting zapped by the big Ascor sunlight they had in one of the studios, so I'm fanatic about the head/socket/power down thing), but I think there might be some safety features in the modern packs - better to do it "right" though.
I've heard really, really good things about Hensel, however, I've never used them. One key thing I've learned over the years is the availability of service when you need it if you're going to be using the stuff hard. Given your school is in/near NJ if I remember correctly, and Dyna is based out of NJ, to me it's kind of a no-brainer that you give Dynalite a look. If you were located in Germany, the answer would obviously be Hensel. I also think Dyna gear is more attractively priced, and that means more spares, which for a gear cage for student use, probably isn't a bad idea because gear will get abused, no matter any best intentions.
-m