No, I haven't tried it yet but for the ribbing I'm using size 8 circular needles and will go to size 11 for the body of the hat. I've knitted since 1971 and haven't ever tried knitting in the round, Magic Loop, etc. since I've never knitted socks or hats that require 4 dpn or Magic Loop. I've always knitted with two straight needles.
Thank you for your help!