Well, i don't own a Shiit, I bought an AR DAC 8, and the Shiit to me was closest to it of the one's we listened to. I also like the Ayre DAC's a great deal. I wouldn't put too much on Stereophile's measurements. Sorry. Unless a DAC is seriously broken they just don't reveal much, and I might say the sam of the reviews. :)
During that same process I also learned I'm not a fan of using a Mac as a source. This is another thing. While I'm usually a big fan of Ayre DAC's the Mac Mini, despite upgrades, made it's top end sound really hard. Point is, even if Stereophile gives it a great review, and mesures fabulously, it may not work well with your source. So it's important to look and listen for yourself.
One of my pet peeves is Stereophile measures USB DAC's under the best possible conditions, while battery operated. Bah. That's like rating a Kayak in a bath tub.
Best,
Erik