I did some benchmarking a while ago on freebsd7 solaris10 and centos4.6, all on the same hardware. At the time, Veritas came out quite well.

on 8 disks, raidz/5:

FreeBSD7: 144/73 MB/s r/w using dd
Solaris10: 150/92
Fedora7 md raid: 164/130
Solaris/veritas: 169/35

raid0/stripe:

FreeBSD7 (zfs): 236/155
Solaris10 (zfs): 169/132
Fedora7 (md0): 259/188
Centos4+vertias: 236/270

Solaris10 (zfs) random write was as fast as veritas and much faster than all the others (~300MB/s versus 150-ish).

I'm now running btrfs and am quite happy with it, should probably run those benchmarks again and clean up the page a bit http://www.crystalconsulting.eu/bench/