Longtime Debian user here. Used Ubuntu and its derivatives for a while but I got sick of it breaking frequently and having to uninstall 90% of the soykaf it comes with just to have a remotely usable system. I moved to Devuan after Debian decided to go with systemd. I currently use Devuan on my main rig and Antix on my secondary.
I have used many other distros including Fedora, Mandrake (remember that?), Gentoo, and Arch. None were ever anywhere near as stable as Debian testing. Gentoo lasted about a week before killing itself, Arch about a month before some update made it unbootable. Everything in Fedora was (and still is) crash-happy and at the time I didn't really like Mandrake.
As for WM's I currently use IceWm but switch to Dwm, Awesome, or WindowMaker if I want something different. >>184
I have used sid many times in the past, I never could keep it from breaking (almost always nvidia's fault), but did have some success with testing. It was still far more stable than Gentoo and Arch though.