These are as solid and substantial as you would hope that they would be.  Should last a lifetime.  I ordered way more than I will need but that's better than needing heel protection but having none.  I walk many miles per day every day and my heels used to wear out way before the shoes did.  Taking them to be resoled just because the heels are worn down is way too expensive and time consuming.  I'd rather just start out with heel protection and skip the trips to the shoemaker.  There is also an unexpected bonus with these strong shiny metal heel plates.  They can be a conversation piece.  "Say, what is that you have on your shoes, I hear something. . .".  I was taken aback the first time someone said something like that.  But now I expect it and enjoy some engaging chit chat!