I agree, I looked at both bags and picked The Brew Bag due to it's lifting lugs making things easier than tying knots around the top of the bag to lift
This is not a "swivel" fitting but a fixed 90 deg elbow - however saying that one can twist the fitting so the answer is a yes to your question i.e. to save space
No need for long lines for the Pluto gun, use this disconnect and you can have the line as short as you want - they do work very well
https://www.kegland.com.au/duotight-8mm-x-flow-control-ball-lock-disconnect-liquid-black-yellow-pok.html