In reply to Andy Farnell:
Did a similar thing - bought two pairs for £35 years ago new. Finally coming to the end of life for the first pair, second pair just broken in.
Not a confident heel for bouldering though, and a bit stiff for grit / font where I prefer the chimeras.
That said they're built excellently and just won't die.
Aren't instinct SRs just the new Stix?
I think what I want is a Scarpa version of the miura vs.