Good question Rhys.
In 2004 I did some work for B&Q, was given four of their trowels, ordinary stainless. By 2008, all but one was broken, on the curved shaft, the piece which joins blade to handle, clean break.
In ten years of constant use I have had damage in a similar place to one copper trowel, but it is still usable with care.
I have also needed to replace the blade of my Hydra hoe, but you can undo the (non-rusting) copper nuts to replace the blade only, no need to throw out the whole tool.
I don’t use my spade much, the odd hole for trees and parsnip removal, it slides into soil so easily that I am always grateful for its quality, the blade is amazingly thin, to save expensive copper I imagine.
Yes expensive. Value to me is good, everyone has to make their own call.