I will start by saying I am no expert. As far as the power rack goes, I believe it has a lot to do with your car and its setup.
I am going with a manual rack in my Mustang, but it should be pretty light up front so steering effort shouldn't be too bad. I have noticed however that it is slightly tougher to turn at low speeds than I like. (Which is all I have ever done with it, pushing it in/out of the garage
) Going back I probably would have ordered a power rack. I would imagine you could also have a better ratio lock to lock with power steering without the effort.
I'm going to start out with the manual rack and see how it goes. Easier install, no lines to run.