I'd say that something like that might work, even if it's somewhat overkill. Just be certain that you're using a 5V output to power the Pi, and that the output is relatively clean. I'm not entirely an electrical engineer - I usually work on the software side - however you can power the Pi using the GPIO pins.
I suggest you check this site out to know exactly where to put your power. Power should be going in on one of the 5V pins (red, top right on the Pinout), and connect the ground on any pin marked black. I'd suggest Physicalphysical Pin 4 and 6, respectively.