Sadly no free Pi Zero for me, I think probably because I'm in Russia and wouldn't get it soon anyway ;)
I'm currently wiring everything for level conversion test of Arduino <-> Pi Zero serial communications. I already confirmed Adafruit's setup works perfectly, but I forgot that I would need reset pin (so additional conversion elements on the board:() and I would need also a power switch 5v-3.3v for Arduino connector. Or a jumper.
Do you have an idea where to put it? :)
I'll have more updates soon. When I figure our what to do with that jumper, ha-ha