Has anyone compared a Supratek preamp to Mantissa?

I have an Audioprism Mantissa, which I really like. But I am curious about the Supratek Chenin or Chardonnay. I have read the thread on Supratek here, and it has me curious if it may be better than my Audioprism. Anyone heard both?
I've never heard the supratek
However I did get Raptor Audio to install v caps in my mantissa and the differences in sound are remarkable