I love those things. I don't think many programs of any kind have the fully-flexible layout and fast-switching Logic has. It's the kind of thing that turns you into a fanatic for two reasons: 1) the feeling of customizing things to be organized just as you want them, and 2) the speed with which you can do the appropriate task. Like right now, I'm swapping between the mostly-default sets #1 (fullscreen Arrange) and #5 (fullscreen Matrix Edit). Most of my customization has been in things like set #9 (mastering setup with all my mastering plugins setup nicely). Why double-click on a sequence in the Arrange when you can select it, hit 5 and be zoomed in on it? Or hit 4 and be zoomed in on it complete with some manipulation tools? (Actually, it's now gotten me thinking that Final Cut Pro has screensets of sorts. But I am doubtful that the switching is as smart as Logic's, mainly because of the Yellow Chain feature that causes zoomed/special windows to track what you're doing.)