fast multi-TB external RAID solution

Our workstation currently includes:

MacPro 3,1: quad core Intel Xeon 3GHz
4 x Hitachi Deskstar 7k1000 at 1TB each

We are looking for a multi-terabyte (2TB+) external solution that will be (in descending order of importance) relatively high speed, cost effective, portable, and low power. We plan to edit fully uncompressed HD 1080p using the internal Hitachi drives (striped). The external drive does not necessarily have to sustain transfer rates for uncompressed HD, but should be fast enough that we can load/offload very large video files without significant wait time (i.e. 100-200 MB/s).

I have been focusing on LaCie solutions for the time being, and see 3 possibilities:
1. Biggest S2S (http://www.lacie.com/us/products/product.htm?pid=10906)
2. 4big Quadra (http://www.lacie.com/us/products/product.htm?pid=11113)
3. several external drives with software RAID (i.e. big disk extreme http://www.lacie.com/us/products/product.htm?pid=10922)

The Biggest S2S claims up to "sustained" 187 MB/s transfer rate over SATAII.

The 4big claims 200-230 MB/s burst speed over eSATA, but this is just the theoretical limit based on "maximum drive speed"

2 big disk extremes (2TB each, on RAID 0) on two different firewire/eSATA connections could be RAIDED together using software? The MacPro has six SATA ports on the board, four in use. The other two could be routed to external drives, but I have the feeling that may bottleneck the SATA controller and slow down the internal drives.


Can anyone offer any insights on the truly sustainable transfer rates of these systems? We have been using MyBook 2TBs over firewire 800 and are not satisfied (both by transfer rate and by a %50 drive failure rate).

 

Thanks for the reply.

I'm pretty sure Fiber is out of my budget for now. We already have an Apple X-Serve 3.2TB on Fiber channel with the co-production machine (quad G5), so if we really need speed, we use that.

Sorry for not mentioning a budget before, but less than $2k for 3-5 TB would be nice.

Of course, an SAS host card (i.e. rocketRAID 2224) at $300, a 4 bay SAS machine (i.e. EnhanceBod E4) for another $400, and 4 x 1TB SAS drives at $300 each sounds about equivalent in price to the Biggest S2S and possibly faster.