There isn’t a single answer, as it depends on the doll’s role in life. For sex, the fixed and fully threaded one is best as it’s too easy for the head to fall off during the action. For photography, the adjustable connector. For just standing around the house as a companion, the quick release but fixed one (2); most of my dolls have come with that as default.
You sent me those Adjustable connectors with my Lirael (Evadora)! I already tried to tighten the screw inside the connector but it seems its already at its end but i can still move the head with only one or two fingers.
Harder to move would be better, but then there is the risk of breaking the thin connection.
Maybe it´s because i´m already used to use more force because of my Zelex they are really hard to move some times.
