The price per gigabyte is steadily going down. The cheapest is currently the Crucial v4 256 GB, which costs £0.52 per GB, based on its average price. If you shop around, you'll undoubtedly find even better deals. It doesn't look like this downwards trend is stopping anytime soon, so it will be interesting to see how SSD prices develop in 2013.
The past year has proven that the performance of SSDs hasn't hit a ceiling yet, and thanks to continual hardware developments we expect this trend to continue as well. The OCZ Vertex 4 for example set a new record in the AS SSD benchmark, only to be beaten by the Plextor M5 Pro which was beaten in its turn by the Samsung 840 Pro. The increase in performance is quite impressive, and is reaching the point where the SATA 600 bus is becoming the bottleneck. It's no surprise then that they're working on the successor in the form of SATA Express, which we will cover in-depth shortly here on Hardware.Info.
Serial ATA 600 has a maximum transfer rate of about 550 MB/s, and particularly with sequential reading this limit is achieved by almost all recent SSDs, or they get very close. Achieving that type of performance with writing data, especially uncompressed data, is a different matter. In this department there is still lots of room for improvement.
We tested 52 SSDs with multiple benchmarks and while the scores differ, we have to emphasize that measurable differences are not the same as noticeable differences. That means that it's almost impossible to tell whether one SSD is faster than another when you are using it on a daily basis. The PCMark 7 benchmark has proven to be the test that correlates the closest to real-life experience. The majority of SSDs that we tested score between 4,900 and 5,600 points in this benchmark, about a 10 percent difference. So if you get an SSD with a score within that range from a reliable brand for a good price, you're in good shape. However, if you use your PC a lot and work with large files, then getting the fastest SSD does have a noticeable if slight impact.