I like manual steering because alot of power steering has a "fake" feel to it. I like steering response not playing a video game with my steering wheel. Not to mention not having an extra pump to run off the motor
Like Ethan said, steering response is the biggie along with less turns in the steering wheel lock to lock and less junk to fail and less junk under the hood. I however am not a fan of manual steering. Nothing like trying to parallel park with manual steering. It probably didn't help that the boricua that I got the truck from had like a 8" grant steering wheel on it.