To get the same results I wanted from trad 1st time cleans, I absolutely need bronze wood pads on unger’s pad holder and I also use unger’s fixi clamp with a cloth wrapped in bronze wool fro getting the corner’s/ hard-to-reach areas of a window to buff out hard water. Boar’s hair got me a long way, but I’ve learned that if it’s a 1st time clean, I need the extra scrubbing power bronze/steel wool offers. Learning how to do it properly took time, but it’s worth it. I typically do two scrubs on 1st time cleans. I go around w/ tap water through my wfp and do a full frame/sill scrub with bronze wool after. Then I do a final scrub/rinse and ‘presto’- perfect windows. That’s just me, hope it helps!
(Edit: I guess they’re not WFP specific accessories, but they certainly are necessary for my style of cleaning )
I would say both are necessary tools to sit in your arsenal.
The little shut off valves are well made and will last long unless you are rough with them. Unfortunately, dragging along cement or up/down stairs will destroy them. Fit them near your source or hold it at all times. I recommend putting UK style foam balls on either side of the valve in order to keep it off the ground.
The dispenser works well. I stopped using it when I started using a backpack sprayer as a soap dispenser.