This is a really good target for your Three Aces success. If you are running a Three Aces Rogue deck anyway, and are also wanting to get in on some damage, I would recommend going for this as a combo piece to that.
Item. Weapon. Firearm. Illicit.
Uses (2 ammo).
Spend 1 ammo: Fight. Instead of its standard damage, this attack deals 1 damage for each point you succeed by (to a minimum of 1, to a maximum of 6). If you fail and would damage another investigator, this attack deals 1 damage for each point you fail by (to a minimum of 1, to a maximum of 6).
The lack of combat boost really limits this card, especially on hard or expert level. If the original Shotgun is also an option, it is usually better, as in comparison it gives +3 twice for only 2 resources more. The sawed-off is only better if you can succeed by 6, which is very difficult indeed for most enemies that you might want a big weapon to fight. For s without access to cards, all but perhaps the most buffed Tony Morgan would prefer Chicago Typewriter and .45 Thompson over the sawed-off, both also capable of dealing 12 damage but much more likely to do so.
This card also deserves consideration in big money rogue decks! At some point Well Connected will boost your to astronomical levels, enough to make this a good tech card for times when you need to fight a big boss at the end of the scenario.
The introduction of Underworld Market makes this card especially good as you can make sure you have it on hand for when you need it (especially with a Fence also living in the market, letting you save playing it until you actually need it). You might even be able to fit a couple Contraband/Contraband in your market deck...