I was quite content with Duckmeisters disclaimer. It told me all that I would want to know. My particular interest was to find if the particular attachment would work for an "ordinary" person. People who work in bike shops are used to making things work and compensating consciously or unconsciously for poor design or manufacturing. Not much help to my wife who is caught out at the start of the Warburton trail and cannot pump up her tyres because the attachment/head will not stay on properly.
Not a good situation, although there were enough cyclists passing to help out - I am sure.
However you relate to my original issue perfectly. The noname and brand name pumps, made of plastic, steel, aluminium etc etc - doesn't matter, the piece that wears is the little rubber thingy that grips the valve, and every time it slips, leaves part of itself in those sharp valve threads - so that sooner rather than later, it will not grip at all. That is why, if bike shops were at all sympathetic to their customers, they would sell a medium priced pump with half a dozen extra rubber seals, and tell the customer the reason. They would sell many more pumps, and generate customer respect and loyalty at the same time. Blybo's post showed us the bike shops do not even stock these items for brand name, and presumably relatively expensive, pumps, but will promise to 'get them in' - the freight and administration is so costly to the customer and the bike shop in this instance, it would pay a shop to stock a pump, and support it properly with replacement parts.
I was told to 'try Repco' - each time I think of it, I am more angry.