I am sorry if I upset you. However I do think you are being a bit tender.
You missed the point of my reply. Amberdale clearly didn’t.
I have no argument with your point about false economy. This isn’t such a case.
As far as I can tell from the information on the tubes, apart from a slight but immaterial difference in the temperature range, the products are identical. Both state they are suitable for use with potable water. The plumbers grease is actually approved by a statutory authority, the other is not.
My conclusion was that there was no discernible difference between the two and hence the high price I paid, which now appears to be mostly due to an excessive markup by the retailer, wasn’t justified.
False economy is quite different to spending more than is necessary. I agree the sum is trivial but there was a genuine enquiry for advice on performance behind my initial post. It appears that there is none.