Dilly, one ladder that is laying on top comes off and the one that is slanted is hinged and would fasten to the ceiling so the poop pit lid could be opened in order to fill with shavings or straw. They roosted on the ladder the way you see them, one slanted up and one horizontal.
Many things will work just fine. Depends on your space and how large your birds are. I prefer the ladder type to the roost pit for my particular birds. They don't have to jump from heights and they can all get up high. The higher ranking birds get higher and the lower ranking ones stay lower, usually. I did have one very high roost across the coop for guineas, too, at one time. Guineas do well with higher roosts and bantams do, too.
Flyman, if you're talking about my ideas, feel free to use anything you see. My coop construction is featured on the BYC coop pages of Large Coops under Clutch Hutch.