I've had two 2-post lifts. The first was a Direct Lift HR8000 and was in my previous garage. I had a 10' ceiling and the lift fit with a few inches to spare. As a result, it had the cables and hose running under a plate which sticks up above the floor and runs between the posts. That was a bit of a pain but the lift was so nice to have, I didn't really mind.
New house has a 12'-4" ceiling so I bought an Atlas 9OHSC
Atlas 9OHSC-SS Light Commercial Grade Two Post Lift | Atlas Automotive Equipment
No plate on the floor with this one. Interestingly, it doesn't really lift much higher than the other one.
I like the access you get to the bottom of the car and the wheels with a 2-post, but I have to admit, I've never had a 4 post.
A couple comments/tips about 2-post lifts:
- almost always need more ceiling height
- require a lot of width - they basically turn a 2 car bay into a 1 car bay
- Need solid concrete at least 4" thick. I drilled test holes to make sure my slab was thick enough
Hope that helps