"Late 2013 Mac Pro SSD in Late 2013 MacBook Pro (Retina)
I just received and installed a new 2013 Mac Pro 512GB SSD (won on eBay - about $400 including shipping and taxes) in my Late 2013 rMBP and it's fast!
BlackMagic Test shows 1,020 MB/s read and write!
It appears to be related to the SSD being 4x PCIe.
It is 4x faster than the 128 GB SSD it replaced.
-Perry"

Nice. (So the OEM 128GB (2x?) SSD was only appx 250MB/sec? - The image you sent later didn't make it through, sorry.) I saw some (512GB IIRC) at eBay earlier this year and heard some used 256GB's being sold from owners that upgraded. (An OWC screenshot showed even the 2013 Mac Pro 256GB SSD was 4x. The Retina MacBook Pro's larger CTO option SSDs are also 4x.)
  

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