Today was the first day Wor Lass would work with me, so early this morning I wired up the second pump and Cleaning Warehouse flow controller; eventually getting it to work.
We have a commercial account of about 20 or so flats just around the corner from us. Wor Lass used the pump powered by a Variflow - which worked more-or-less with no problems, and I used the pump controlled with one of these:

I calibrated it as per the instructions and all I got was a slow flow even at full whack. I struggled with it because I wanted Wor Lass to get some practise on the pole (phnaar phnaar), which she did and she's mightily impressed with a van mount and the SLX. She actually seemed - for one brief moment - to get excited about the possibilities we have about working in this new way, but it passed quickly.
And at the end of the day, I sacked the Cleaning Warehouse flow controller for one of these:

It cost a tenner from our local plumbing place!
So we have two pumps, one with a variflow and the other with a tap before the pump to control the flow, and it seems to work nicely, but it hasn't been 'field tested' yet; only fannied about with outside my house.
Y'knaa, at one point today, using the Cleaning Warehouse flow controller, I rolled out the full 100 meters of hose, tried to start work, but got only a trickle. After walking back and forth to the van TWICE (so 500 meters - half-a-ruddy-kilometre), I eventually got enough of a flow to work!

Hopefully this won't happen again with the tap!
There were probably a few other minor traumas.
Hopefully, tomorrow will be a trauma free day!