just got mine in, just started testing but have 3 newpacs running @ 350 MHz
using Sipolar 10 Port 5V 20Amp USB hub: https://www.eyeboot.com/sipolar-10-port-usb-hub.html



average speed is approx 70 GH/pc, very stable, no zombies, and this is with 0 v.core tweaking. these can go a lot faster.
just make sure you are using fans or some sort of cooling system...

Update

Now running @ 500MHz for over 110 GH per miner!!!



NEWPACs are available for order now, in-stock over here:
https://www.eyeboot.com/gekkoscience-bitcoin-usb-stick-miner-newpac-btc.html