I think how well it does will depend a lot on the amount of media coverage the KS gets, more than anything. The games were actually received pretty well. SRR has a 76 on Metacritic, DF: DC has an 87 and most of the user reviews there and elsewhere seem to be in agreement with that. Moreover, one of the biggest criticisms of SRR was the save system, which was eventually rectified with a patch. But all the people who liked their games certainly aren't going to back if they don't know about it. If all the sites that gave DF positive reviews think this KS is newsworthy, it could do pretty well. They deserve to break Torment's record, and while that probably won't happen I hope they are able to get enough to sustain and even expand their company to continue making Shadowrun games and perhaps even other RPGs for years to come.
Aside from the fact that I really love Dragonfall, the other thing I really love about HBS is that they seem to be striving to constantly improve. They have been humble enough to admit that their games aren't perfect and actually take players constructive criticism into consideration. Even when people have been a bit unreasonable with their expectations or downright nasty, it seems like they're looking for what they can do better, rather than just being defensive / dismissive. Compare that to several of the other developers who have recently released KS games and then actually blamed people for being too harsh in reviews, and "costing them the sales they need" to actually finish their game.
There have certainly been a few bumps in the road. "Dead Man's Switch" was fairly short and too linear (although it also had a lot less filler content than many longer RPGs). There was the limited save system and their initial deal with M$ that would've had any future SR games be Steam exclusives. But HBS learned from their mistakes and fixed the problems. They even did the Director's Cut with Dragonfall turning it into a standalone and giving it to everyone who had the expansion for free.
So yeah, I'm going to back the drek out of their next game. I expect they'll probably have some pretty interesting stretch goals as well.