[Welsh Anorak]

Absolutely right - you don't want pro gear to be off the road or performing less than perfectly.
However, for domestic and semi-pro equipment common sense needs to be used. Older Hunts or Callins parts are almost guaranteed to be faulty, but later Japanese capacitors in small signal locations were pretty indestructible. In fact when I've checked I've often found the ESR of the old part to be better than a new one out of the drawer.
I think we're agreed here, and despair the attitude that if you change all the capacitors in any piece of equipment all faults will magically disappear!
With experience you get to know which to change and which to leave alone. In the OP's case, there will be very little to change.