Disenchanted with ZFS; alternatives?

[Kirk Strauser]

I have ZFS on my 7.1-PRERELEASE system, and while it does some spiffy things, 
in general I'm a bit underwhelmed.

PROS:

  Adding new filesystems on a whim is really nice.

  It has a lot of really cool other features that I will probably never need.

CONS:

  I have nearly 3GB of wired RAM, but it doesn't seem to be all that fast.  
For example, starting an Amanda backup on a UFS2 filesystem would get through 
the "estimate" phase almost instantly on a system that had been up for several 
days because of cached filesystem data.  On ZFS, it still limps along even if I 
just finished the last backup a few minutes earlier.

  Other than saying "I'm using ZFS", I don't seem to have much to show for it.

WTF:

  "Raidz  and  top-level vdevs cannot be removed from a pool."


At this point, I'm almost ready to go back to good ol' UFS2, but I'd hate to 
give up that easy addition of new filesystems.  I *could* have a single 700GB 
root FS but that just doesn't seem right.  Are there any good, tested GEOM-
based ways of getting that functionality, perhaps along the lines of using 
something like gvirstor and growfs as needed?

- Kirk