gmirror of zfs mirror

[Dick Hoogendijk]

  I'm convinced that ZFS mirroring is far better than gmirroring, but 
the latter uses much less memory (I think).
My server has 3Gb and is solely used as server (web, files/nfs/samba, 
dns, mail).
The data is serves does not change much, so I would think the data 
integrity checks of ZFS although useful do not serve a very high 
purpose. If a disk goes bad it can be replaced using gmirror and/or ZFS.

Why would it be the preferred way to use ZFS over gmirror?
I know ZFS (I come from opensolaris). I'm not that familiar with 
gmirror. Hence the doubts..;-)