Hands or Feet for Accept and Reject?
Slam Buttons and Pedal Three both exist to make accept and reject faster than reaching for a key, but they ask for different body parts: Slam Buttons wants a hand, Pedal Three wants a foot. If you want zero hand movement during review, buy Pedal Three; if you'd rather keep both feet still and just hit something satisfying with a hand, buy Slam Buttons.
What each one physically is
Slam Buttons is a pair of full-size arcade buttons on a single cream plate, wired, with genuine arcade switches, a long throw and a loud bottom-out. They're macro-definable but almost always mapped to accept and reject, and they're large enough to hit without looking, which is the actual ergonomic argument for them. Pedal Three is three foot pedals on a curved steel base, also wired, and the common mapping, accept, reject, hold-to-talk, covers almost the entire review loop without a single hand leaving the keyboard.
The real trade-off: desk space vs. a foot habit
Slam Buttons sit on the desk near your hands, so they cost you desk real estate but ask nothing of your feet, there's no new coordination to learn, you just reach over and slap one. Pedal Three lives on the floor and costs you no desk space at all, but it does ask you to build a foot-tap habit, which takes a session or two to feel automatic. If your desk is already crowded, that alone might decide it. If your desk is fine but you want literally zero hand movement during a long review session, the pedal wins outright, Slam Buttons still require moving a hand off the keyboard, even if the target is huge and satisfying to hit.
What Pedal Three does that Slam Buttons can't
Pedal Three has a third pedal free for hold-to-talk, so the same device that handles your accept/reject also handles dictation. Slam Buttons is exactly two buttons and nothing else, there's no path to a third action without a different product.
What Slam Buttons does that Pedal Three can't
Nothing functional, honestly, but the tactile case is real. A big arcade button with genuine travel and an audible bottom-out is more satisfying to hit than a pedal tap or a keystroke, and for some people that satisfaction is what keeps review sessions from feeling like a chore. That's a real reason to buy something, just not a technical one.
Who should buy neither
If you review agent output only a few times per session, the speed difference between either of these and a keyboard shortcut isn't going to be noticeable. Both of these earn their keep at hundreds of accept/reject decisions a day, not a dozen, and buying either one for occasional use is paying for a habit you don't actually have yet.
See how Slam Buttons compares to a macropad instead in Slam Buttons vs. EM Mini Pad, or browse the full comparison hub. Setup notes: Slam Buttons for Cursor.