I purchased a Mk3 aqua-dapter last week found it very easy to fit.
today i used it for the first time, i normally hold the pole about a 1/4 way up and found i was stretching to turn it off. I was using a tap before attached to a belt.
I will keep going and try it out for this week.
Not 100% convinced it is for me.
I think they are like MARMITE " you either love them or hate them"