A servo is a good way to go if you want to control how far the grill opens. I think others have mentioned it, perhaps not in this thread specifically.
The main benefit of using a power door lock actuator is the price. The servo deal looks to be ~$25 from your links. You can get a power door lock actuator on ebay for $4 shipped, and the h-bridge on mouser for $5 plus shipping.
NEW CAR UNIVERSAL POWER DOOR LOCK ACTUATOR MOTOR 12 volt U.S.A seller | eBay
TLE52052XK Infineon Technologies | Mouser
I happened to already have the door lock actuator, so all I needed was an h-bridge.
Options are always good though!
