Silicon Power has a unique external drive that is capable of taking a beating, surviving a dip in the pool and still performing quite well. When it comes to performance, or more specifically claimed performance, we would like to see Silicon Power do a better job of informing consumers of the actual capabilities of their products.
When it comes to actual transfer rate performance, the Silicon Image Armor A80 can read and write data at 100MB/s under ideal conditions. During the worst of times the drive can only perform these tasks at just over 50MB/s. If you are looking for more performance, look elsewhere as we have already tested portable USB 3.0 drives that perform better and cost less.
The drives that we have tested do fall well short of the mil spec housing that Silicon Power uses and that does add value, especially if you travel with portable storage regularly. The included USB 3.0 short cable as well as the physical size of the Armor A80 make it truly portable. The system isn't as portable as a thumb drive, but you are also not going to get up to 640GB of capacity out of the thumb drive at this time either.
When it comes to pricing I am still not sold on the 640GB model listing at close to 170 USD. The Samsung Spinpoint drive is retailing for around 70 USD at Newegg at the time of writing, so that leaves the housing costing right around 100 USD. That is one expensive USB 3.0 enclosure no matter how much abuse it can take. With USB 3.0 enclosures now selling for as low as 21 USD at Newegg, it is safe to say you understand our reservations on pricing.