If you’re new to the technology, a bit of explanation might be in order. We’ll take you through it from the beginning, so that you fully understand the various aspects of this technology, why it’s important, and what it can do for you. To that end, let’s start with DAS.

What is DAS?
Simply put, it stands for “Direct-Attached Storage.” In simplest form then, it’s an external hard drive, but the solutions we’re talking about here are much more than that. Broadly speaking, DAS solutions can be broken into the following categories:

  • Desktop solutions – these devices require an external power source to function.
  • Portable – these devices draw power from the system they’re hooked up to. They need no external power.
  • NAS/SAN – This is a very specialized DAS-style solution. What makes NAS solutions unique is that they have built-in Ethernet connection capabilities, because they are designed for use in a network environment.

Where DAS is concerned, there are two standards to pay attention to. USB 3.0, and Thunderbolt. USB is the more common standard, and Thunderbolt is native to Apple hardware.

What is RAID?
Another acronym, this one standing for “Redundant Array of Independent Disks.” RAID storage arrays are important for a number of reasons, but chiefly, we’re talking about data integrity and performance issues. Simply put, if you’re in a data intensive business, you need it. There’s a lot more that can be said on the topic (indeed, whole books have been written on this, but you can start here for an excellent synopsis if you need further details: http://wolfcrow.com/blog/afraid-a-raid-primer/ )

Is Thunderbolt Better than USB 3.0?
“Better” is a subjective term. It’s different, and it’s faster (USB 3.0 generally tops out at about 500MB/s, while Thunderbolt tops out at a little more than double that—1.2GB/s, however the new version of Thunderbolt2 runs at maximum of 20Gbps. It doesn’t necessarily matter that Thunderbolt isn’t as “universal” as the USB3.0 solution, because we’re talking about buying equipment based on your system.

If you’re using a fairly modern piece of Apple hardware like the latest Mac Pro, then you can pick and choose here:

 


See the whole table here.

Comparison Notes:
For each of the products below, we’re zeroing in on a few key features. These will be:

  • Size range (how much storage is possible)
  • Number of bays
  • Number of ports (Thunderbolt 1, 2, and USB 3.0)
  • Maximum data transfer speed the unit has tested out at
  • Warranty length
  • Price
  • Most commonly mentioned user pros
  • Most commonly mentioned user cons

 

Areca ARC-8050 Thunderbolt 2
Number of bays: 8
Number of ports (Thunderbolt 1, 2, and USB 3.0) (0,2,0)
Maximum speed: 900MB/s
Warranty length: 3 years
Price: $2159 (enclosure only)
Pros: Simple GUI
Cons: Screw mounted drives, no independent power switch

Caldigit T3
Size range 2.88-12TB
Number of bays: 3
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,0)
Maximum speed: 850MB/s
Warranty length: 1 year
Price: 9TB ($1199)
Pros: Fast and quiet

Drobo 5D
Size range (open ended)
Number of bays: 5
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,1)
Maximum speed: 350MB/s
Warranty length: 2 years
Price: $959 (enclosure only)
Pros: Good GUI, Great storage expansion capabilities
Cons: Painfully slow

G-Technology G-RAID with Thunderbolt
Size range: 4-8tB
Number of bays: 2
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,0)
Maximum speed: 320 MB/s
Warranty length: 3 years
Price: 4TB $839
Pros: Quiet and reliable
Cons: Painfully slow, not very expandable

La Cie 2Big RAID
Size range: 4-10TB
Number of bays: 2
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,0)
Maximum speed: 320MB/s
Warranty length: 3 years
Price: 4TB $599
Pros: No tools required to swap drives
Cons: Bulky/heavy compared to other models

La Cie 5Big RAID
Size range: 10-25TB
Number of bays: 5
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,0)
Maximum speed: 780MB/s
Warranty length: 3 years
Price: 10TB $1229
Pros: No tools required to swap drives
Cons: Bulky/heavy compared to other models

OWC Mercury Elite Pro Dual Drive
Size range: 0-8TB
Number of bays: 4
Number of ports (Thunderbolt 1, 2, and USB 3.0) (2,0,0)
Maximum speed: 850MB/s
Warranty length: 3 years
Price $699 (enclosure only)
Pros: Fast
Cons: Noisy

OWC ThunderBay IV
Number of bays: 4
Number of ports (Thunderbolt 1, 2, and USB 3.0)(2,0,0)
Maximum speed: 850MB/s
Warranty length: 3 years
Price $699 (enclosure only)
Pros: Fast
Cons: Loud

Promise Technology Pegasus 2 R4
Size range: 0-8TB
Number of bays: 4
Number of ports (Thunderbolt 1, 2, and USB 3.0) (0,2,0)
Maximum speed: 500MB/s
Warranty length: 2 years
Price: $789 (enclosure only)
Pros: Reliable
Cons: Slowish, not very user friendly

Promise Technology Pegasus 2 R6
Size range: 12-18TB
Number of bays: 6
Number of ports (Thunderbolt 1, 2, and USB 3.0)(0,2,0)
Maximum speed: 900MB/s
Warranty length: 2 years
Price: 12TB $2689
Pros: Fast
Cons: Not very user friendly

Promise Technology Pegasus 2 R8
Size range: 24-32TB
Number of bays: 8
Number of ports (Thunderbolt 1, 2, and USB 3.0)(0,2,0)
Maximum speed: 900MB/s
Warranty length: 2 years
Price: 24TB $4189
Pros: Fast
Cons: Not very user friendly

Assessing a “winner”
Different features will be important to different people. That said, we can make some general recommendations based on our collected stats.

Maximum Storage & Maximum Speed
If maximum possible storage is important to you, then you’re going to want either the Areca ARC-8050, or the Pegasus 2 R8 (both topping out at 32TB). Note that the Pegasus is an all in one solution. The drives are included in the cost, whereas the Areca price is for the enclosure only. You’ll need to buy the drives to bring it up to 32TB storage.
The winners don’t change much if speed is your biggest requirement. The Areca is still in the running, as are the Pegasus 2 R8 and its smaller cousin, the Pegasus 2 R6. Honorable mention to OWC’s ThunderBay IV and Caldigit, both of which clock in just behind these.

Warranty Length
If this is your biggest concern, then you’ve got a lot of choices, with OWC, LaCie, G-Technology and Areca all offering impressive 3 year warranties on their products.

Versatility
The only two models that offer both Thunderbolt and USB3.0 ports are the Drobo and the OWC Mercury Elite. Bear in mind that these two also have the slowest transfer speeds of any drive on the list.

Convenience
If you’re looking for an all-in-one solution and don’t want to have to buy anything else, then you’ll be interested in looking at Caldigit, G-Technology, La Cie, or the Pegasus R6/R8.

Price
If price is your biggest concern, then you’re going to be looking at the smaller, 2-bay models first, which sees you paying close attention to G-Technology, LaCie, and OWC’s Mercury Elite Pro.