Here is a comparison from my testing and that done by Vapor. Vapor had a modified OCZ V2 drive with LTT disabled and itwas using Hynix nand. Mine was a V3 using IMFT nand. SF drives stop at MWI 10, whilst it appears the threshold for the 520 is 0. Too early to be sure but it certainly looks like the 520 is able to write more before a drop in the MWI is recorded.

(I did not have a smart logger at the time so the values are not precise)

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