Thunderbolt products are not cheap, and the LaCie 2big Thunderbolt is no exception. The price of the 4TB version is £410. Soon there will be a version with two 4TB disks as well, for a total of 8TB of storage. You also need a Thunderbolt cable of course, which will set you back about £40. The WD My Book Thunderbolt Duo 4 TB is slightly more affordable with an average price of £396.
If you want to spend the money to get a Thunderbolt disk, then this LaCie is the better choice because of it superior performance. It's a bit of a shame that the included software is so basic, requiring you to use the Disk Utility in Max OSX. That is why it earns the Hardware.Info Silver Award.
LaCie 2big Thunderbolt
The LaCie 2big Thunderbolt comes with a three-year warranty.