Can some advanced user here list reasons why bazaar might be better
than mercurial, for the usage described briefly below.

Or, if merc would, in fact, be the better tool.

Usage scenario:

One repo each for hosts on home lan.  At least the linux/opensolaris
hosts. Which amounts to some 8 hosts.  (Some are vmware guests on
windows machines).  

Not much need for repos on windows machines here.  Or at least, I've
never really felt the urge to do programming or experimentation on the
windows machines, beyond installing various bits of software.

1) (Probably) Main usage is keeping versions of quite a few OS related
   `rc' files.  Quite a few under /etc but also /boot and the
   directories that contain my 150 or so scripts. Also a few under
   /var.

   Each repo is kept in a directory structure roughly mirroring the
   host it is on.

   Till now I've always done this with cvs... so that is my sole
   exprience with vcs tools.
   
   I had a cvsroot on the server that included all hosts, then on each
   host a checked out module for that host.

2) I keep an area which is really an nfs mounted zfs filesystem from
   opensolaris server for various projects or scripting experiments
   etc.
   
   I think I want to start keeping that as a repo and tracking the
   assorted scripting experiments or experimental usage of tools I
   don't know how to use yet.  Some, maybe even most tracked files may
   be pretty short lived, or may set in the repo unchanged, once
   experimentation is over.

   Sooner or later, I think there will come a time when I want to see
   previous versions of some of this stuff.

So those 2 points would be about it for me.  Very light usage and also
single user usage.