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happywonton wrote:Solid state drives are not only more efficient, they're also faster and lighter, making the entire package more appealing. Of course, it has to be a LOT more appealing, as the flash drive ads $600 to the price of the Portégé R500 with a regular hard drive.

It's quite a premium, but for the truly power-conscious, high-end consumer, there's finally a solid state option. And there's a lot of room for improvement, as flash drives are getting bigger and cheaper every day. Don't be surprised if Mac heads in this direction fairly soon. The increase in speed and efficiency alone are making this a really hot area for development right now.

Price - As of early 2007, flash memory prices are still considerably higher per gigabyte than those of comparable conventional hard drives - around $8 per GB compared to about $0.25 for mechanical drives.

Capacity - The capacity of SSDs tends to be significantly smaller than the capacity of HDDs.

Lower recoverability - After mechanical failure the data is completely lost as the cell is destroyed, while if normal HDD suffers mechanical failure the data is often recoverable using expert help. Subsequent investigations in to this field, however, have found that data can be recovered from SSD memory. Investigation into this from Disklabs [8] Data Recovery means that SSD memory can be read, re-written and sampled back together. It is true that there may be some data loss, but it is also true that often, all data can be retreived.

Vulnerability against certain types of effects, including abrupt power loss (especially DRAM based SSDs), magnetic fields and electric/static charges compared to normal HDDs (which store the data inside a Faraday cage).

Slower than conventional disks on sequential I/O, the latest perpendicular hard disks doing about 150 Megabytes/sec read, with the latest SSDs doing about 100 Megabytes/sec read.

Limited write cycles. Typical Flash storage will typically wear out after 100,000-300,000 write cycles, while high endurance Flash storage is often marketed with endurance of 1-5 million write cycles (many log files, file allocation tables, and other commonly used parts of the file system exceed this over the lifetime of a computer). Special file systems or firmware designs can mitigate this problem by spreading writes over the entire device, rather than rewriting files in place. [2]