Intel's X25-M solid-state drive has generally aced all testing, with its combination of super-high read and write speeds, which is why SSD-loving geeks were so disturbed by PC Perspective's long-term performance analysis. According to their findings, Intel's file controller - which cycles through available flash cells progressively, so as to avoid wearing out regularly-accessed blocks - results in a significant slow-down of performance due to the OS being unable to keep track of fragmentation. Now Intel are denying that the PC Perspective testing - which simulated a longer life-cycle - is in fact an accurate representation of an X25-M's use.
"We found that a ‘used’ X25-M will always perform worse than a ‘new’ one, regardless of any adaptive algorithms that may be at play. We also found that in some cases, the drive would drop to significantly below manufacturer specs" PC Perspective
The reviewer attempted to mimic the lifespan of a drive, in a setup which Intel claim to be unable to reproduce. In that setup, while the controller was able to track fragmentation, the host OS was not, and the former did a poor job of managing any sort of defragmentation process. The end result is a permanently under-performing drive, which can only be fixed by fully formating it and starting again from scratch.
Intel, for their part, aren't discounting the possibility that the X25-M SSD controller needs tweaking, and are apparently working with PC Perspective to see whether their testing is accurate. If so, and the SSD is shown to have a fragmentation problem, they will likely release a firmware update to address it.