I've been an erstwhile FreeBSD user since v2.x (ca. December 1996),
running FreeBSD on my own machines since v4.x (ca 2001), and started
using it as my primary laptop/desktop daily driver since v5.3 (ca.
November 2004). Prior to that, SunOS/Solaris was my drug of choice.
In the past, I would update the OS and ports religiously, sometimes
rebuilding world and packages on a weekly basis. I've never once
experienced any bumpiness between v5.x and v8.x (or any other version,
but see my comments on v13 below). The OS has always been rock solid.
I have occasionally experienced some package issues, usually when
upgrading a port that had lagging dependencies -- some packages written
in PHP come readily to mind. The number of times this has happened is
more than 2 and less than 6, and in each of those cases, using
portdowngrade and waiting it out a few weeks did the trick.
Apart from OS-independent hardware issues, the only real FreeBSD issue
that I've ever encountered was in the v12->v13 upgrade. If you were
running ZFS, there was a gpart bootcode command you needed to run as
part of the upgrade process, which I sometimes forgot to do, which
caused the post-upgrade reboot to hang. Normally this wouldn't be a big
deal, you just insert the rescue CD and run the command and be on your
way 2 minutes later; but at that time I had a number of my servers
running on a VPS provider that didn't allow you to mount your own ISO,
so I had to wipe the machine and reinstall the OS from scratch and
restore stuff from backups. I don't really count this as a FreeBSD issue
per se, just an obtuse service provider. (I've since moved most of my
digital properties oceans away from that company.)
Nowadays I upgrade the OS and packages far less frequently. I upgrade
the OS with every minor release and also if there are any security
issues that affect me. I upgrade the packages every couple of months, or
if there is a bugfix that affects me, or if I need a new feature only
available in a newer release.
Since I started using it, there have been a number of developments that
have made my FreeBSD life so much better: cperciva's portsnap and
freebsd-update, pkg-ng, and of course the biggest one: ZFS. All of these
allow me to maintain and upgrade the systems very easily.
I stick with FreeBSD because of its consistency and ease of use, so I'd
be curious to know what you mean by "bumpy"?
In the past, I would update the OS and ports religiously, sometimes rebuilding world and packages on a weekly basis. I've never once experienced any bumpiness between v5.x and v8.x (or any other version, but see my comments on v13 below). The OS has always been rock solid.
I have occasionally experienced some package issues, usually when upgrading a port that had lagging dependencies -- some packages written in PHP come readily to mind. The number of times this has happened is more than 2 and less than 6, and in each of those cases, using portdowngrade and waiting it out a few weeks did the trick.
Apart from OS-independent hardware issues, the only real FreeBSD issue that I've ever encountered was in the v12->v13 upgrade. If you were running ZFS, there was a gpart bootcode command you needed to run as part of the upgrade process, which I sometimes forgot to do, which caused the post-upgrade reboot to hang. Normally this wouldn't be a big deal, you just insert the rescue CD and run the command and be on your way 2 minutes later; but at that time I had a number of my servers running on a VPS provider that didn't allow you to mount your own ISO, so I had to wipe the machine and reinstall the OS from scratch and restore stuff from backups. I don't really count this as a FreeBSD issue per se, just an obtuse service provider. (I've since moved most of my digital properties oceans away from that company.)
Nowadays I upgrade the OS and packages far less frequently. I upgrade the OS with every minor release and also if there are any security issues that affect me. I upgrade the packages every couple of months, or if there is a bugfix that affects me, or if I need a new feature only available in a newer release.
Since I started using it, there have been a number of developments that have made my FreeBSD life so much better: cperciva's portsnap and freebsd-update, pkg-ng, and of course the biggest one: ZFS. All of these allow me to maintain and upgrade the systems very easily.
I stick with FreeBSD because of its consistency and ease of use, so I'd be curious to know what you mean by "bumpy"?