I believe... there is no performance benefit to going with a mechanical array... only a cost benefit. IMHO, you can easily build a solid state storage solution that will outperform any mechanical drive setup... it will just cost more.
I responded in the other thread, but it will depend on the specific SSD (i.e. sequential writes are anywhere from 70 - 220MB/s IIRC), and the one that stands out to me for such use, is the 1TB Colossus (super fast sequential write + high capacity). Also keep in mind, I've assisted users with 12TB arrays for video/grahpics work, and am accustomed to large capacity really being on the large side for a single user system.
Unfortunately, I checked Amazon yesterday on the 1TB Colossus, and they're priced just under $4300USD.
Now keep in mind, that I try to figure in a balance of price/performance. It's just the way I have to think, as budgets are never truly unlimited. If there's a real need, then the buget will get pushed to the correct level to acommodate specific setups, but not without a serious need to do so.
So for now, that means mechanical = best-bang-for-the-funds.
Given that cost doesn't appear to be much of an issue and storage requirements are relatively modest, the ideal solution is to use a couple of Intel SSD's in RAID0 for your OS/Apps and then get a couple of high capacity OCZ Vertex or other Indilinx based SSD's for your media storage which have extremely strong sequential read/write speeds. That would blow the doors off of even a 4 drive mechanical array.
I don't see it that way, but I'm thinking of at least 4TB for the large array. If it can be done with less, maybe it's a bit more plausible, but it still doesn't hold the value.
You could get a faster system that way though, as say 4x drives (even small capacity models that can do 200+MB/s for sequential writes, can only be touched by SAS - Cheetah 15K.7's). They're not as expensive though, and still offer better value IMO.
Now if said SSD array were meant for random access (i.e. a database as well as OS or apps type usage), it may make more sense. I'd need specifics on the usage.
It's always the usage specifics anyway.
There's certainly no need for a separate scratch volume when using SSD's
No there isn't. Enough RAM will mitigate the need anyway, no matter the disk tech used.
Given the write cycle issues with SSD, users would need to be really careful to make sure they've adequate unused space if they do want to run the scratch of it, or run the risk of premature death. If say it's a single 80GB used for the OS and apps, I'd put it on the mechanical, if used.
Just keep in mind that 3 SSDs per array is going to max out the ICH.
Yep. If someone is really going to use SSD's for the graphics files, I'd think they'd be better off with a RAID card for both this reason (can exceed the 660MB/s ICH10R limit), and the ability to have additional ports for expansion later.
Another option to consider if you have money growing on a tree in your back yard is a PCIe RAID card to run your SSD arrays on.
See above.
OP, you are correct about G2 Intel drives having issue with 10.6.2, so you could either track down some G1 drives or stick with 10.6.1 until the issue gets addressed.
Given the issues with 10.6.2, I'd think 10.6.1 would be the better choice no matter if on the logic board (SSD or mechanical) or for RAID cards, as there's been problems there too (major stability problems = high drop-out frequency).
