SFS filesystem is superior to FFS in terms of speed and reliability, but requires 68020 or better processor (tbc. not 68000/68010). It does currently lack a few features that FFS has, so if you are not sure whether something can be done on SFS volumes, consult the documentation or use another filesystem in that case. That's acceptable because it is considered beta.
Perhaps SFS isn't recommended in those cases where a successful uninterrupted boot is more important than anything (unsupervised/remote use), as it handles error situations more carefully and will impede the boot at least if the volume which is being booted from, is affected. For most users/uses however, SFS is a lot more attractive than FFS.
P.S. In the past I've lost a small amount of files that I did myself, so: always backup these at least.
