I didn't realize how much a guy would use a brake until I built my hydraulic one. For little stuff, I did pick up a small box & pan brake from Enco. It is the 16 ga. x 4 ft.

This one was a bunch cheaper than the one you're looking at. From the Enco stuff I've bought, most of it seems to come from the same place that Harbor Freight gets theirs. This brake is supposed to be good for 4' of 16 ga. I have clamped a foot of 14 ga. in it and broke that stuff. Machine seems to be up to the task, but it takes a lot of muscle to bend even a foot. I'm guessing a 4 foot 12 ga. bend would take a bunch of muscle power. My hydraulic brake gets those jobs