2c: Select your storage: Hard drive or SSD?
Instead of swapping the EliteBook's rather slow 320GB hard drive with a larger one, I decided to replace it with a 480GB solid-state drive (SSD), which is roughly five times faster at reading and writing data, can take more abuse and uses less power than rotating media does. Since much of my current work now resides in the cloud, the storage space should be quite sufficient.
On the other hand, an SSD costs roughly five to six times more than a hard drive for a lot less storage space. For instance, the 2.5-in. Crucial M500 SSD I installed cost me $370 versus about $60 for a 500GB hard drive. So it all depends on your own needs.