Whether an SSD is cost-effective in practice always depends on how it is to be used. Usually, however, speed alone is more than a good reason to rely on SSDs. Even a slow SSD is significantly faster than most high-quality hard drives. In practice, the latter can achieve data rates of about 100 MB/s. SSDs, on the other hand, are often slowed down only by the interface and achieve data rates of 450 MB/s or more. This means that files can be transferred about four times faster. The differences become even more obvious when transferring many small files. With a hard disk, the read head has to jump back and forth all the time, which leads to long waiting times. Since there is no read head on an SSD, copy operations work much faster than on a magnetic disk.
The advantages of SSDs are also noticeable when used externally. Even hundreds of gigabytes of data are quickly backed up with an external SSD. This is a great help when frequent backups have to be made. Not only are the waiting times for copying shorter, but the computer is also relieved and can release its resources for other tasks. The purchase of an external SSD is therefore always rewarding if it is used regularly. Only if an external data carrier is to be used as a so-called "data grave", the advantages of SSDs are not to be felt too strongly. If, for example, you only want to archive films or similar files, you won't feel any speed advantages when retrieving them.
The fact that conventional hard disks still hold such a large position in the mass market today can only be attributed to their price. This is where such hard disks still play their greatest trumph, because consumers pay significantly less per gigabyte than with an SSD. This makes hard disks a good choice whenever terabytes of data need to be stored, for example on a server or NAS. In everyday use, however, the advantages of SSD hard disks clearly predominate, so that the use of such a data carrier is almost always recommended.
Prices for SSDs have also been falling steadily in recent years. Meanwhile, some high-quality models are already available for less than 0.10 Euro per gigabyte. The price difference to hard disks is likely to become smaller and smaller in the next few years. Therefore, it will only be a matter of time before SSDs finally replace classic hard disks.
The additional price for an SSD in comparison to a hard disk may be unpleasant at first. In practice, however, it is almost always worth it to spend some money for the advantages of modern data carriers. Users benefit in every conceivable way. SSDs are faster, more compact, more energy-efficient and lighter than almost any hard drive. This leads to a multitude of advantages in both stationary and mobile operation. For this reason, external SSDs are always recommended when a data storage device is in regular use. Today, hard disks are still the better option only for long-term archiving, but only because of the lower price. In all other categories, SSDs are far superior to hard disks.