M.2 is quickly gaining popularity thanks to its small size and power requirements as well as the possible speed increase and other features.  Transcend's 128GB MTS800 drive features fill AES encryption, wear levelling and garbage collection as well as something new, StaticDataRefresh Technology.  That is their name for a process which automatically restores the charge levels in the NAND cells which both prevents errors from accumulating as well as performance reduction over time.  M.2 drives do come with a price premium, the 128GB model is available for $76 on Amazon but the performance is impressive, the lowest transfer speed The SSD Review saw during their testing was 265.61MB/s.

"We have been seeing more M.2 SSDs lately, a lot of which are companies’ first steps into the market since the form factor is so new. They have been designed to meet strict size requirements and allow for greater flexibility in product development. They are the perfect fit for mobile devices with their compact size and light weight."

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