01Swing beam or guillotine
A swing beam blade moves on an arc with a fixed rake angle, and its blades usually have two cutting edges. A guillotine moves straight down, lets you change the rake, and its blades usually have four. The guillotine costs more and bows narrow strips less.
02Blade gap setting
The gap must change with thickness or the edge tears and the blade chips. A hand lever with a scale, or a motorised setting driven by the controller: ask which.
03Back gauge
Most listings named a basic one axis NC controller. Ask gauge travel, ball screw or not, and whether it retracts for long sheets.
04Blade material and spares
Ask the blade steel grade and hardness, and price a second set now. Blades are the wear part.
05Guarding and sheet support
Finger guard, hold-downs, and a rear light curtain or fence. Thin sheet also needs rear support, or the cut length drifts.