RE: which is better
I usually use tree screws (or 40penny nails) because they're incredibly cheap-what I really prefer to do is use a climbing belt and kick spikes, or use trees with a lot of limbs so I can just climb up-they help to conceal me in my stand as well...the belt/kick spike set up keeps people from getting stealing my stand, or hunting it without my permission.
I've really liked using climbers, but finding a tree that has no limbs high enough to make climbing handy here in Kansas isn't easy-it's NOT handy to have to un-hitch a climber to manuover around 15 branches on your way up.
I don't really like ladder stands, they're probably as sturdy as they come, I just don't like carrying that much metal afield, and there's no hiding a ladder. I've made some "non-typical" ladder stands, they mount sideways compared to typical ones, the ladder runs up to the side of the stand, so it's closer to the tree...one of them I made so that the ladder was against the tree off to the side of the stand, basically a free hanging stand with a fixed ladder.