Your first sour should not be a bad beer. It is a journey and do you want to start the journey with a broken wheel?
But give it a try if you have tons of spare kegs. You can pull a sample at any time, just be kind to the pedicle. This will intro o2, which is not a super horrible thing in small amounts. I sour in kegs by closing all ports except the gas in. Over the screw I throw on a small stopper, think a number 2, and insert a single piece airlock.
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