Not the most efficient use of XP. Compare this to Time Warp; both allow you to draw an extra chaos token, but "Eat lead!" only works for Firearm attacks, and forces you to spend ammo on top of that, and has to be played in advance (before you know whether you'll need the extra token or not).
Now, you can get even more tokens from "Eat lead!" if you so desire—but how many tokens do you really need? There’s major diminishing returns here, as each chaos token pulled after the first contributes less and less to your odds of success. Furthermore, ammo is precious. Even spending 1 extra hurts quite a bit, let alone 2 or 3. This really limits the effectiveness of this card with Shotgun or Lightning Gun, since the ammo is just so precious. It's a bit better with the .32 Colt, but I don't think I'd rush out and spend my XP on that.
I’m not saying this card has no place at all. "Worse than Time Warp" is not the same thing as unplayable. A janky Double or Nothing/Shotgun/Extra Ammunition deck is probably pretty excited to see this card. And with Stick to the Plan, for which both Extra Ammunition and "Eat lead!" are valid targets, these elaborate multi-card combos are more achievable than they first appear. But generally speaking, this card isn’t that powerful for 2 XP. That’s disappointing, since Firearms could have used a stronger buff than this.