I've continued to rely on the Walker Audio SST. (I do use the Extreme SST version, and find it makes a nice improvement over the regular SST, but your comments about price are well noted.) This week I removed some tubes on which I'd treated the pins with SST four years ago. The SST had dried as it is designed to do, had not migrated, and cleaned off easily with isopropyl alcohol revealing bright shiny metal underneath. Still highly recommended here.
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