G-Technology, a company owned by Hitachi, has released an updated model of their G-RAID solution, which now adds Thunderbolt support. Essentially the G-RAID Thunderbolt is equivalent to the regular G-RAID but features two Thunderbolt ports instead of the eSATA, FireWire, and USB ports that are found in the regular version. From inside they are the same: both utilize two SATA 3Gb/s Hitachi Deskstar hard drives, which can be configured in either RAID 0 or RAID 1 mode.

Typical of most Thunderbolt devices, the G-RAID Thunderbolt has two Thunderbolt ports to enable daisy-chaining. G-Technology quotes a sustained throughput of 280MB/s, but since the performance of hard drives is heavily dependent on the areal density, the maximum performance of the 4TB and 6TB models is likely slower.

StorageReview is also reporting that they saw an unreleased G-DRIVE with Thunderbolt support. G-DRIVE is G-RAID's little brother that has a single 3.5" hard drive. Unfortunately, there is no information on its specifications or availability.

There are quite a few Thunderbolt products out there so let's recap the external Thunderbolt storage offerings quickly. Right now there are five brands with products available for the masses: Promise, LaCie, Western Digital, Seagate and G-Technology. Most of these are external storage solutions with two or more hard drives, but there are simpler products like Seagate's GoFlex adapter that turns any GoFlex drive into a Thunderbolt drive. The table below compares products from the aforementioned companies:

If we only look at price per GB, Seagate's GoFlex Desk drives with the Thunderbolt adapter are the cheapest--especially the 3TB and 4TB models are very affordable when compared to other options. However, keep in mind that GoFlex Desk drives feature only a single 3.5" hard drive, whereas all other solutions have at least two 2.5" or 3.5" drives. Running two drives in RAID 0 increases the performance (particularly sequential transfer rates), hence the GoFlex Desk should be the slowest drives in the comparison.

3.5" hard drives top out at 4TB at the moment and thus one has to look into multi-drive solutions if more than 4TB is needed. At 6TB, Western Digital's My Book Thunderbolt Duo series offers the best price/capacity ratio. In terms of performance, however, it's rated as slower than G-Technology's and LaCie's offerings--though we need to emphasize that the performance ratings are from manufacturers' sites and may hence not be completely accurate.

G-Technology's advantage is the fact that they are the only company (along with Seagate) that is using 4TB hard drives. As Seagate does not offer any dual-drive solutions, G-Technology is the only company that offers an 8TB dual-drive product. $1000 is definitely expensive but it's $800 less than what Promise asks for their 8TB version of the Pegasus R4. However, Promise uses four 2TB drives and there is support for RAID 5 and 6 as well, so Pegasus and G-RAID aren't strictly comparable.

All in all, there are definitely a lot more products than there were a bit over a year ago when Thunderbolt launched, but personally I expected more. It has been over a year and yet the cheapest Thunderbolt storage solution will still set you back over $300. I give Seagate credit for bringing an adapter to the market instead of dedicated products like other manufacturers, but $190 for an adapter (or $100 for the 2.5" adapter) is an awful lot. For $190 you can get a 3TB USB 3.0 hard drive that will perform the same due to the fact that the hard drive is the bottleneck. Of course, the advantages of Thunderbolt lie elsewhere but given the current products, most of Thunderbolt's potential is being missed.