There is a review at 3dscanexpert which states the following:

According to the manufacturer the SP’s accuracy specification is better because

The parts specification on the SP is different.
The SP uses a more robust calibration plate, which accuracy is certificated by a serious accuracy verification process.
The manufacturing and test process of each SP is also following the accuracy verification requirement of metrology-level scanners.
Since both scanners have the same pair of 1.3 megapixel cameras I wasn’t sure how the SP could deliver higher accuracy but according to Shining 3D the “SP uses a senior arithmetic to ensure better accuracy” hence the necessity of a more powerful Nvidia GPU.
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So the cameras are the same and the plate to calibrate is a little bit sturdier. The SP also has some markers on the turntable. But that's it.
The speed of the turntable is the same.

It all comes down to the software and exposure times and algorithms which are different for the SP.

-e