Speidel Pressure Relief Valve

[MotoGP1000]

Has anyone used the Ball Lock Pressure Relief Valve on their Speidel Fermentors?

Im wondering if this takes the place of the airlock or if its a last minute switch when performing the closed transfer.

Also... the Speidel seems to have a lot of head space. Any issues with oxygen cracking the lid and plopping in dry hops ?

thanks,