With a 12% hill, get a 4x4, you won't regret it. Even just in general driving you will notice the difference (improvement in handling).
I have a Subaru Forester 4x4 estate that's getting a bit long in the tooth now ('03, 145k miles) and will be replacing it with a Skoda Yeti Outdoor 4x4 next year. Excellent mpg, build quality, reliability, and towing and off road capabilities.