I leveled from 40 to 50 largely with Broonmark, mostly because I liked the idea of having a brutal homicidal animal at my command. He's actually pretty effective at holding aggro. I'd basically stick him on the silver/elite, and scythe through the lesser enemies (doing my best to CC them with Smash, Force Scream, and Ravage, to help Broonmark survive). On tougher single mobs we'd trade aggro, and again I'd CC with Force Choke, Force Push, etc. in order to prolong his life. Geared, I can see him being quite sturdy, though at base tank companions are not very sturdy.

Honestly, as a Powertech BH I don't even find myself firing my blaster all that often. Most of my attacks make use of the left-hand weapons platform, so using a single-handed blaster pistol makes more sense. Rifles would still be cool, though.