ASM - hardware mirroring vs. Oracle mirroring

I am starting to investigate ASM as a part of a potential 8.1.7.4 to 10g
upgrade on Solaris (SunOs 5.9).  Oracle's documentation seems to have a
bias toward having the ASM instance handle the mirroring while our UNIX
support people would prefer to do it at the hardware level.  Which is
preferable and what factors would push a decision in one direction or
the other?

Thanks,
Peter Schauss

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