I've only dipped my toes in so far, but a really great thing is you can have multiple full length-half width windows open if you need multiple references to whatever you're working on.

Simple example: you're designing a middleware app. You can set up the windows

backend code | your code | frontend code

or

documentation | your code | reference code

In a tiler you'd probably have to make them half-length, switch them out, put them on other workspaces... In a scrolling wm you can just scroll back and forth, with your work still on your screen:

[ documentation | your code ]

scroll right

[ your code | reference code ]

scroll left

[ documentation | your code ]

(of course you can set this up with more than two columns)

I find it's a really really nice and smooth workflow