>I'd guess disk speed would be an issue. Yes of course RAID can speed up disk access. But practically? Buying new disk drives every so often as rotational speeds, caching and interface speeds improve would outperform an old RAID setup. We found EIDE and RAID 0 far outperforms a 2 year old SCSI RAID 5 system!

You can't compare between RAID 0 and RAID 5. It's entirely different. RAID 0 is pure performance, while RAID 5 is pure protection.

Regards