Just checked mines on number 4 varistream i am pumping 2 lpm
I prefer 5 and even 6 with minibore hose. The rinse is great but I waste water during the scrubbing phase. i use 4 most of the time and 3 when doing wooden windows.
I would really like the remote controller Spring has with 2 different flow settings. Wash a few windows on low flow, press the remote and trigger the controller into a fast flow for rinsing.
You don't really need that if you use the kink/pinch hose method as can vary the flow to yer hearts content
Still all the same they do look handy to be able to turn the pump on/off saves walking back to the van that's if the wifi is in range
Its what works for you. My fingers don't work so well any more so I can't crimp the hose. I lost the nerves in my right thumb about 12 years ago when I tried to cut it off with an angle grinder. It doesn't always respond to instructions and with very little feeling, I have to watch it working.

I dragged on/off taps along the ground for a few years before the first Aquadapter arrived. My back aches after a short while cleaning and as the day wears on I was not able to keep bending down to pick the tap up to switch it off. Its even worse now.
The moment the A/D hit the market it was a god send to me. Some don't like the coil of the hose. I love it as I hook the brush underneath it to pick it up - saves me bending down. If there isn't a coil, one can be created very quick but moving a shoe across it.
If you ask me, the A/D is still the best accessory invention for our wfp market to date. I appreciate that Peter Fogwill had an equivalent before this using the same principle, but Steven ran with the concept and made it 100 times better - sorry Peter.