Plextor M6M Series
The Plextor M6M series is based on the same technology as the M6S series except with a different form factor. Whereas the M6S is a 2.5" drive, the M6M comes in mini-SATA (mSATA) packaging, which is more suited for ultra-mobile devices and compact Mini-ITX builds.
Back in September of 2012 we got our first look at an mSATA SSD when Crucial provided a sample of its m4 mSATA 256GB drive, which offered the same performance as the larger 2.5" version but was capable of fitting in much smaller devices.
The M6M is a newer, faster product that has a lot less competition than the 2.5" version. Plextor is offering capacities as small as 64GB while it is still possible to get a 512GB version as well. The 64GB model costs $70 which is a rather steep $1.09 per gigabyte. The 128GB model costs the same as the 2.5" M6S version at $100 while the 256GB and 512GB models are fetching a slight price premium of $10 - $20.
At $170, the 256GB model faces the Crucial M550 256GB and Samsung 840 Evo 250GB, while the Crucial M500 240GB and Mushkin Enhanced Atlas 240GB cost just $130. The read/write specifications are similar to the M6S series though interestingly the write speeds of the 128GB and 256GB models are slightly higher, 40MBs for the 128GB drive and 20MBs for the 256GB version.
As expected, the 64GB model suffers massively in terms of write performance and Plextor claims just 160MB/s, less than half that of the 128GB model. For a mere $30 discount, you would have to be mad to purchase the 64GB model over the slightly more expensive 128GB model.
Utilizing the mSATA SSD form factor means that the M6M series measures just 50.8mm long, 29.8mm wide and 3.6mm thick. Furthermore, the SSD weighs just 10 grams -- even the bigger model. The M6M series has the same 72TB write rating as the M6S series as well as the three-year warranty.