SSDs have many advantages over their mechanical predecessors (HDDs). As they have no moving parts, they are far less prone to damage. They use less electrical power, meaning that laptops can run cooler and with less fan noise. And they are a lot faster, often running 5-10 times as fast, giving a significant boost to computer performance. It all sounds very good, but are there any downsides? Yes, there are two main considerations. Firstly, they are more expensive than HDDs. For instance, a standard 500GB laptop drive can be purchased for about £40 whereas an SSD of similar capacity is around £200. Secondly - and partly following on from the first point - they are not readily available in high capacities.
However, as time progresses, SSDs will take over from HDDs. It won't happen overnight - HDDs are a mature, low-cost, established product. But SSDs will get progressively cheaper and, at some point in a few years time, will overtake HDDs. They will also improve, both in performance and reliability. Although all SSDs are intrinsically faster than HDDs, what most people don't appreciate is that the low capacity ones are significantly slower than the higher capacity models. This is partly a function of price: low capacity drives have a lower price point and this results in compromises and cost-cutting on the internal controllers. However, some manufacturers (for instance Samsung) now have high-end electronics and controllers in even their low cost models and this approach will eventually become the norm.