RAID 5 external hard drive 6TB recommendation

[digicube]

I would like to purchase a RAID 5 external hard drive 6TB or more. Can you recommend me some? I could find any on Newegg. Most on google are custom built, so I might as well built it myself and save some money. This is the external case I'm looking at. EnhanceBOX E8 MS (Mini SAS) http://www.enhance-tech.com/products/desktop/E8_MS.html
The performance of the mini-SAS seems to be faster than Multilane and Port Multiplier version. Also which setup would be better? The RAID card in the external case or in my pc? All external hard drives on the market has the raid controller in the external case, so it's just plug n play with FW400/800/USB2.0.

 

[MerlinRML]

Port Multiplier is nice because it's cheap. It offers 4 or 5 disks connected to a single 3Gbps SATA connection. The downside is that most motherboard controllers do not support port multiplier, so you need an additional SATA/RAID controller that supports it. Most of these controllers are based on a Silicon Image chip, and I think Marvell may support it as well. With 1TB disks and probable RAID overhead, you are probably going to need 2 enclosures to achieve your 6TB of space. Every cheap vendor basically uses the same SIIG RAID controller and board in the chassis. The only different is in the look/feel of the chassis.

SAS expansion requires a separate SAS/RAID controller. It offers a 12Gbps connection to as many as 127 devices. It also offers things like multiple controllers and failover. It's a much more interesting solution, but it's also more expensive. An enclosure that can support 8 disks is probably going to cost half as much as your disks. I've looked at products from Supermicro, AIC/Xtore for SAS expansion enclosures.

 

[digicube]

Thanks for the recommendation but I've already purchased EnhanceBOX E8 MS (Mini SAS) http://www.enhance-tech.com/pr...desktop/E8_Series.html
The website mentions that mini-SAS has the best performance while PM has the lowest, why is that?

 

[digicube]

Just built it. IT'S FAST. 100MB/s write, twice the speed of FW800. I get 70MB/s on my SATA 3.0Gbps single hard drives when transferring files from the RAID 5, so the read rate is fast too.

PS: Mini SAS cable are expensive, 2m cable is $75-$100 each.