> My own personal experience with Arch & Debian Sid is that Sid is noticeably more stable than Arch, long term.
I have the exact opposite experience, I used to use sid and had to do full-blown reinstall every couple months because e.g. dpkg would break too much and I wouldn't be able to install anything, or once, even boot and ended up migrating to arch despite the warnings - never had to reinstall the distro once since then
I'd been using Debian sid for almost 10 years and now use Arch for more than 5 years. Sid is definitely much more stable, as in "not requiring manual interventions", than Arch is. In fact it was actually a bit "too stable" for my taste because it effectively becomes frozen together with 'testing' right before a new 'stable' gets released.
That said, never had to reinstall either of them. Had my system broken by pacman in ways dpkg would handle much better, but it was fixable anyway.
I've been running a mixed testing/sid install since 2005 and not once did I have to reinstall. Even managed to cross-grade from i386 to amd64 a couple years ago.
Do you remember when that happened? I vaguely remember that I used to experience problems installing packages in Aptitude and it would make me "fix" them without a way forward that I liked, but that was years ago.
eh, I switched to arch around.... 2013/2014 ? after an especially bad crash with sid. Never used aptitude, only apt-get. Since then I'm carrying the same "distro" from computer to computer.
Aptitude is mostly a front-end to apt-get, but if you try to install some impossible combination of packages or get your packages in a weird state, aptitude offers solutions to fix it.
I have the exact opposite experience, I used to use sid and had to do full-blown reinstall every couple months because e.g. dpkg would break too much and I wouldn't be able to install anything, or once, even boot and ended up migrating to arch despite the warnings - never had to reinstall the distro once since then