Hi Colin. neighbour ( well, same county )
Actually in those pictures, the porty was at the other end of the hoses.

I cant see the customers ever catching me out though.
When I use the porty and scrubba together I normally go at about 100 - 150 psi. Any more than that and you go through a lot more water for no tangable benifit. The use of a good prespray, heat and dwell time ( not that I am aiming to teach you to suck eggs ) is half the battle.
I am not a great fan of extracta porty machines. This has a lot to do with me spending a long chunk of my working life in the high tech end of the composites industry ( closed mould process ) . So when I see GRP products I can't help being critical. ( Unfair I know )
However I do beleive that there isn't a better powered extraction head available for use with portable machine anywhere. I would go as far as to say they are a must have item.