Hi Michael, 

I've done FFT benchmarks for MATLAB R2017b + Advanpix (version 4.4.5.12699) vs. Mathematica 11.2 vs. C + MPFT library back in 2017-2018 using 

4 core Intel Core i7 3770K @ 4.5Ghz, 10-core Intel Xeon E5-2690v2 @ 3Ghz and 20 cores among two Intel Xeon E5-2690v4 @ 2.6Ghz 

If interested, you can take a look at my results at https://www.researchgate.net/project/Multiprecision-FFT-benchmark

Sorry for the blog format, but It's what I have.